JP2010209081A - THERAPEUTIC METHOD USING ANTI-ErbB2 ANTIBODY - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a therapeutic method for diseases based on the overexpression of human ErbB2 gene, as the ErbB2 gene encoding a transmembrane glycoprotein receptor of 185kd (p185HER2) relating to epidermal growth factor receptor (EGFR) has been found to be overexpressed in human cancer. <P>SOLUTION: The therapeutic method for human patients diagnosed as a disease caused by the overexpression of ErbB2 is to administer an effective amount of a combination of an anti-ErbB2 antibody and a chemotherapeutic agent except anthracycline. As the diseases, the method is effective to benign and malignant tumors, particularly breast tumors. As the chemotherapeutic agent, a taxoid, particularly paclitaxel or docetaxel is preferable. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

Detailed Description of the Invention

(Field of Invention)
The present invention relates to a method for the treatment of diseases characterized by overexpression of ErbB2. More particularly, the present invention relates to humans who are susceptible to or have been diagnosed with a cancer that overexpresses ErbB2, using a combination of an anti-ErbB2 antibody and an anthracycline, such as a chemotherapeutic agent other than doxorubicin or epirubicin. Relates to a method for treating patients.

(Background of the invention)
Proto-oncogenes encoding growth factors and growth factor receptors have been identified as playing an important role in the causes of various human malignancies, including breast cancer. The human ErbB2 gene (erbB2, also known as her2, or c-erbB-2), which encodes the 185 kd transmembrane glycoprotein receptor (p185 ^HER2 ) associated with the epidermal growth factor receptor (EGFR), is Overexpression has been found in about 25-30% (Slamon et al., Science 235: 177-182 [1987]; Slamon et al., Science 244: 707-712 [1989]).

  Some evidence supports the direct role of ErbB2 in the pathogenicity and clinical virulence of tumors that overexpress ErbB2. Introducing ErbB2 into non-neoplastic cells has been shown to cause its malignant transformation (Hudziak et al., Proc. Natl. Acad. Sci. USA 84: 7159-7163 [1987]; DiFiore et al., Science 237: 78-182 [1897]). Breast tumors have been found to develop in transgenic mice expressing HER2 (Guy et al., Proc. Natl. Acad. Sci. USA 89: 10578-10582 [1992]).

  A protein encoded by an antibody against the human erbB2 protein product and a rat equivalent of the erbB2 gene (neu) has been described. Drebin et al., Cell 41: 695-706 (1985) refers to an IgG2a monoclonal antibody against the rat neu gene product. This antibody, called 7.16.4, causes down-modulation of cell surface p185 expression in B104-1-1 cells (NIH-3T3 cells transfected with neu proto-oncogene) and inhibits colony formation of these cells . In Drebin et al., PNAS (USA) 83: 9129-9133 (1986), the 7.16.4 antibody was injected into neu transformed NIH-3T3 cells implanted in nude mice as well as rat neuroblastoma cells (neu oncogene first. It has been shown to inhibit tumorigenic growth (from isolated). Drebin et al., Oncogene 2: 387-394 (1988), discusses the production of antibody panels against rat neu gene products. All antibodies have been found to exert a cytostatic effect on the growth of neu transformed cells suspended in soft agar. Antibodies of the IgM, IgG2a and IgG2b isotypes could mediate significant in vitro lysis of neu transformed cells in the presence of complement, although both antibodies have high levels of antibody-dependent cytotoxic activity of neu transformed cells (ADCC) could not be mediated. Derbin et al., Oncogene 2: 273-277 (1988), reported that a mixture of antibodies reactive with two different regions on the p185 molecule is a synergistic anti-antigenic agent against neu transformed NIH-3T3 cells transplanted into nude mice. It has been reported to produce a tumor effect. The biological effects of anti-neu antibodies are reviewed in Myers et al., Meth. Enzym. 198: 277-290 (1991). See also International Publication No. 94/22478 published on October 13, 1994.

Hudziak et al., Mol. Cell. Biol. 9 (3): 1165-1172 (1989) describes the production of an anti-ErbB2 antibody panel characterized using the human breast tumor cell line SKBR3. . Following exposure to the antibody, relative cell proliferation of SKRB3 cells was measured by monolayer crystal violet staining after 72 hours. Using this assay, the maximum degree of inhibition was obtained with an antibody called 4D5, which inhibited cell proliferation by 56%. The other antibodies in the panel containing 7C2 and 7F3 reduced cell proliferation to a lesser extent in this assay. Hudziak et al. Conclude that the effect of the 4D5 antibody on SKBR3 cells is mitotic rather than cytotoxic, because SKBR3 cells resumed growth at a nearly normal rate following removal of the antibody from the medium. Yes. Furthermore, antibody 4D5 has been found to sensitize p185 ^erbB2 overexpressing breast tumor cell lines to the cytotoxic effect of TNF-α. See also International Publication No. 89/06692, published July 27, 1989. Anti-ErbB2 antibodies investigated by Hudziak et al. Are Fendly et al., Cancer Research 50: 1550-1558 (1990); Kots et al., In Vitro 26 (3): 59A (1990); Sraup et al., Growth Regulation 1: 72-82. (1991); Shepard et al., J. Clin. Immunol. 11 (3): 117-127 (1991); Kumar et al., Mol. Cell. Biol. 11 (2): 979-986 (1991); Lewis et al., Cancer. Immunol. Immunother. 37: 255-263 (1993); Pietras et al., Oncogene 9: 1829-1838 (1994); Vitetta et al., Cancer Research 54: 5301-5309 (1994); Sliwkowski et al., J. Biol. Chem. 269 (20): 14661-14665 (1994); Scott et al., J. Biol. Chem. 266: 14300-5 (1991); and D'souza et al., Proc. Natl. Acad. Sci. 91: 7202-7206 ( (1994) is further characterized.

  Tagliabue et al., Int. J. Cancer 47: 933-937 (1991) describes two antibodies selected by their responsiveness to ErbB2 overexpressing lung adenocarcinoma cell line (Calu-3). Yes. One of the antibodies called MGR3 has been found to internalize, induce phosphorylation of ErbB2, and inhibit tumor cell growth in vitro.

  McKenzie et al., Oncogene 4: 543-548 (1989) produced a panel of anti-ErbB2 antibodies with various epitope specificities, including an antibody designated TA1. This TA1 antibody has been found to induce accelerated endocytosis of ErbB2 (Maier et al., Cancer Res. 51: 5361-5369 [1991]). Bacus et al., Molecular Carcinogenesis 3: 350-362 (1990) report that TA1 antibody induces maturation of breast cancer cell lines AU-565 (overexpressing erbB2 gene) and MCF-7 (not overexpressing). Has been. It has been found that inhibition of growth and acquisition of the mature phenotype in these cells is accompanied by a decrease in ErbB2 receptor levels at the cell surface and a transient increase in levels in the cytoplasm.

  Stancovski et al., PNAS (USA) 88: 8691-8695 (1991) produced a panel of anti-ErbB2 antibodies that were injected intraperitoneally into nude mice and transformed by overexpression of the erbB2 gene. Their effects on tumor growth were evaluated. Four antibodies detected varying levels of tumor inhibition, but one of the antibodies (N28) consistently stimulated tumor growth. Monoclonal antibody N28 induced significant phosphorylation of the ErbB2 receptor, whereas the other four antibodies were shown to generally have low or no phosphorylation-inducing activity. The effect of anti-ErbB2 antibody on the growth of SKBR3 cells was also evaluated. In this SKBR3 cell proliferation assay, the two antibodies (N12 and N29) caused a decrease in cell proliferation relative to the control. The authors of this paper evaluated the ability of various antibodies to induce in vitro cytolysis through antibody-mediated cell-dependent cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). It was concluded that the inhibitory function of the antibody is not significantly attributed to CDC or ADCC.

  Bacus et al., Cancer Research 52: 2580-2589 (1992) further characterized the antibodies described in the previous paragraphs Stancovski et al. And Bacus et al. (1990). The intraperitoneal study of Stancovski et al. Was expanded to evaluate the effect of antibodies after intravenous injection into nude mice with mouse fibroblasts overexpressing human ErbB2. As found in their earlier studies, N28 accelerated tumor growth, whereas N12 and N29 significantly inhibited the growth of ErbB2-expressing cells. In addition, partial tumor inhibition was also observed with the N24 antibody. Bacus et al. Further demonstrated the ability of antibodies to promote the mature phenotype in human breast cancer cell lines AU-565 and MDA-MB453 (overexpressing ErbB2) and MCF-7 (including low levels of the receptor). Tested. Bacus et al. Found that there is a correlation between tumor inhibition and cell differentiation in vivo; tumor stimulating antibody N28 has no effect on differentiation, and the tumor inhibitory effects of N12, N29 and N24 antibodies are There was a correlation with the degree of differentiation induced.

  In Xu et al., Int. J. Cancer 53: 401-408 (1993), a panel of anti-ErbB2 antibodies to epitope binding specificity, and (depending on the individual antibody or combination) SKBR3 cell anchorage independence and anchorage dependence. The ability to inhibit sexual growth, modulate cell surface ErbB2, and inhibit ligand-stimulated anchorage independent growth was evaluated. See also International Publication No. 94/00136, published Jan. 6, 1994, and Kasprzyk et al., Cancer Research 52: 2771-2776 (1992) related to the combination of anti-ErbB2 antibodies. Other anti-ErbB2 antibodies are described by Hancock et al., Cancer Res. 51: 4575-4580 (1991); Shawver et al., Cancer Res. 54: 1367-1373 (1994); Arteaga et al., Cancer Res. 54: 3758-3765 (1994). ); And Harwerth et al., J. Biol. Chem. 267: 15160-15167 (1992).

Recombinant humanized anti-ErbB2 monoclonal antibody (humanized version of rhuMAb HER2 or Herceptin (HERCEPTIN ^R) mouse termed anti-ErbB2 antibody 4D5) are widespread anti-cancer treatment of ErbB2-overexpressing metastatic breast cancers that have received before the It was clinically active in patients with (Baselga et al., J. Clin. Oncol. 14: 737-744 [1996]).

ErbB2 overexpression is generally considered to be a poor prognostic predictor, particularly in patients with primary disease involving axillary lymph nodes (Slamon et al., [1987] and [1989], supra ; Ravdin and Chamness, Gene 159: 19-27 [1995]; and Hynes and Stern, Biochim Biophys Acta 1198: 165-184 [1994]), CMF (cyclophosphamide, methotrexate and fluorouracil) and anthracyclines (Baselga et al., Oncology 11 (3 Suppl 1): 43-48 [1997]), associated with susceptibility and / or resistance to hormonal therapy and chemotherapy. However, despite ErbB2 overexpression associated with poor prognosis, the likelihood of HER2-positive patients who responded clinically to treatment with taxanes was more than three times that of HER2-negative patients (Id.). rhuMab HER2 has been shown to increase the activity of paclitaxel [Taxol ^R ] and doxorubicin against breast cancer xenografts in nude mice injected with BT-474 human breast cancer cells expressing high levels of HER2 (Baselga et al., Breast Cancer, Proceeding of ASCO, vol.13, Abstract 53 [1994]).

(Summary of Invention)
The present invention relates to a method for treating diseases characterized by overexpression of ErbB2, and treatment with anti-ErbB2 antibodies generally significantly enhances the clinical benefit when using chemotherapeutic agents, while anthracycline derivatives Based on the recognition that myocardial dysfunction syndrome, which has been observed as a side effect, is increased by administration of anti-ErbB2 antibody.

  Therefore, the present invention provides a therapeutically effective amount of a combination of an anti-ErbB2 antibody and a chemotherapeutic agent other than an anthracycline derivative such as doxorubicin or epirubicin in the absence of an anthracycline derivative to a human patient. A method of treating a human patient prone to or diagnosed with a disease characterized by overexpression of the ErbB2 receptor, comprising:

Said disease is preferably a benign or malignant tumor characterized by overexpression of ErbB2 receptor, for example cancer, especially breast cancer, squamous cell carcinoma, small cell lung cancer, non-small cell lung cancer, gastrointestinal cancer, pancreatic cancer, glioblastoma Cell tumor, cervical cancer, ovarian cancer, liver cancer, bladder cancer, hepatoma, colorectal cancer, colorectal cancer, endometrial cancer, salivary gland cancer, kidney cancer, liver cancer, prostate cancer, spawning cancer, thyroid cancer Hepatic carcinoma and various types of head and neck cancer. The chemotherapeutic agent is preferably a taxoid, such as Taxol ^R (paclitaxel) or a Taxol ^R derivative.

  Although the antiproliferative effect is sufficient, in a preferred embodiment, the anti-ErbB2 antibody can induce cell death or can induce apoptosis. Preferably, the anti-ErbB2 is bound to the extracellular domain of the ErbB2 receptor, preferably to epitope 4D5 or 3H within the ErbB2 extracellular domain sequence. More preferably, the antibody is antibody 4D5, most preferably in humanized form.

The method of the invention is particularly suitable for the treatment of breast or ovarian cancer characterized by overexpression of ErbB2 receptor.
In other aspects, the invention treats a container, a composition containing an anti-ErbB2 antibody in the composition in the container, and optionally a condition wherein the composition is characterized by overexpression of the ErbB2 receptor. A label on or associated with the container, and a package insert containing instructions to avoid the use of anthracycline-type chemotherapeutic agents in combination with the composition. Regarding manufactured goods.

Detailed Description of Preferred Embodiments
I. Definitions The terms “HER2”, “ErbB2”, and “c-Erb-B2” are used interchangeably. Unless indicated otherwise, the terms “ErbB2”, “c-Erb-B2” and “HER2” as used herein refer to human proteins, “her2”, “erbB2” and “c-erb” -B2 "refers to the human gene. Human erbB2 gene and ErbB2 protein are described, for example, in Semba et al., PNAS (USA) 82: 6497-6501 (1985) and Yamamoto et al., Nature 319: 230-234 (1986) (Genbank accession number X03363). ErbB2 has four domains (domains 1-4).

  “Epitope 4D5” is a region in the extracellular domain of ErbB2 to which antibody 4D5 (ATCC CRL 10463) binds. This epitope is close to the transmembrane region of ErbB2. To screen for antibodies that bind to the 4D5 epitope, a conventional cross-blocking assay described, for example, in Antibodies, A Laboratory Manual, Cold Spring Harbor Laboratory, Harlow and David Lane (1988) can be performed. Alternatively, whether the antibody binds to a 4D5 epitope of ErbB2 (ie, from about residue 529, eg, from about residue 561 to about residue 625, any one or more residues in the region containing it) Epitope mapping can also be performed (see FIG. 1).

  “Epitope 3H4” is a region in the extracellular domain of ErbB2 to which antibody 3H4 binds. This epitope is shown in FIG. 1 and comprises residues from about 541 to about 599 of the amino acid sequence of the extracellular domain of ErbB2.

  “Epitope 7C2 / 7F3” is the N-terminal region of the extracellular domain of ErbB2 to which 7C2 and / or 7F3 antibodies (each deposited with the following ATCC) bind. To screen for antibodies that bind to the 7C2 / 7F3 epitope, a conventional cross-blocking assay described, for example, in Antibodies, A Laboratory Manual, Cold Spring Harbor Laboratory, Harlow and David Lane (1988) can be performed. Alternatively, check whether the antibody binds to the 7C2 / 7F3 epitope of ErbB2 (ie, any one or more residues in the region from about residue 22 to about residue 53 of ErbB2; SEQ ID NO: 2) In order to do this, epitope mapping can also be performed.

  The terms “inducing cell death” or “capable of inducing cell death” refer to the ability of an antibody to render a living cell non-viable. The term “cell” as used herein refers to a cell that expresses the ErbB2 receptor, particularly a cell that overexpresses the ErbB2 receptor. Cells that “overexpress” ErbB2 have significantly higher ErbB2 levels than normal compared to non-cancerous cells of the same tissue type. Preferably the cell is a cancer cell such as a breast, ovary, stomach, endometrium, salivary gland, lung, kidney, large intestine, thyroid, pancreas or bladder cell. In vitro, the cells can be SKBR3, BT474, Calu3, MDA-MB-453, MDA-MB-361 or SKOV3 cells. In vitro cell death is determined in the absence of complement and immune effector cells and is distinguished from cell death induced by antibody-dependent cytotoxicity (ADCC) or complement-dependent cytotoxicity (CDC). The Thus, assays for cell death can be performed using heat inactivated serum (ie, in the absence of complement) and in the absence of immune effector cells. To determine whether an antibody is capable of inducing cell death, it is assessed by incorporation of propidium iodide (PI), trypan blue (see Moore et al., Cytotechnology 17: 1-11 [1995]) or 7AAD. The degree of membrane integrity loss is assessed relative to untreated cells. Preferred cell death-inducing antibodies are those that induce PI uptake in the “PI uptake assay in BT474 cells”.

  The terms “inducing apoptosis” or “capable of inducing apoptosis” refer to Annexin V binding, DNA fragmentation, cell contraction, endoplasmic reticulum expansion, cell fragmentation, and / or membrane vesicle formation (apoptotic body). The ability of the antibody to induce programmed cell death as determined by The cell is one that overexpresses the ErbB2 receptor. Preferably, the “cell” is a tumor cell, such as a breast, ovary, stomach, uterine body, salivary gland, lung, kidney, large intestine, thyroid, pancreas or bladder cell. In vitro, the cells can be SKBR3, BT474, Calu3 cells, MDA-MB-453, MDA-MB-361 or SKOV3 cells. Various methods are available to evaluate cellular events associated with apoptosis. For example, phosphatidylserine (PS) translocation can be measured by annexin binding; DNA fragmentation can be assessed by DNA laddering as disclosed in the Examples below; cell nucleus associated with DNA fragmentation / Chromatite aggregation can be assessed by any increase in hypodiploid cells. Preferably, in the “Annexin binding assay using BT474 cells”, the antibody that induces apoptosis is about 2-50 times, preferably about 5-50 times, most preferably about 10-50 times annexin of untreated cells. The result is that it induces binding (see below).

  Occasionally, pro-apoptotic antibodies will block HRG binding / activation of the ErbB2 / ErbB3 complex (eg, 7F3 antibody). In other situations, the antibody does not significantly block activation of the ErbB2 / ErbB3 receptor complex by HRG (eg, 7C2). Furthermore, the antibody can be such as 7C2 that induces apoptosis but does not induce a large reduction in the percentage of cells in the S phase (eg, about 0-10% of the percentage of these cells relative to the control). % Induces only a reduction in%).

  Antibodies of interest are those such as 7C2 that specifically bind to human ErbB2 but do not significantly cross-react with other proteins such as those encoded by erbB1, erbB3 and / or erbB4 genes . Occasionally, antibodies do not significantly cross-react with rat neu protein, as described, for example, in Schecter et al., Nature 312: 513 (1984) and Drebin et al., Nature 312: 545-548 (1984). In such embodiments, the degree of binding of antibodies to these proteins (eg, cell surface binding to endogenous receptors) is about 10% as measured by fluorescence activated cell sorting (FACS) analysis or radioimmunoprecipitation (RIA). Would be less.

“Heregulin” (HRG) as used herein refers to a polypeptide that activates the ErbB2-ErbB3 and ErbB2-ErbB4 protein complexes (ie, phosphorylation of tyrosine residues of the complex when bound thereto) ). Various heregulin polypeptides encompassed by this term are described, for example, in Holmes et al., Science, 256: 1205-1210 (1992); International Publication 92/20798; Wen et al., Mol. Cell. Biol., 14 (3) : 1909-1919 (1994); and Marchionni et al., Nature, 362: 312-318 (1993). The term includes naturally occurring variants of HRG polypeptides and / or biologically active fragments thereof, eg, EGF-like domain fragments thereof (eg, HRGβ1 _177-244 ).

  “ErbB2-ErbB3 protein complex” and “ErbB2-ErbB4 protein complex” are ErbB2 receptors and non-covalently linked oligomers of ErbB3 receptors or ErbB4 receptors, respectively. Complexes are formed when cells expressing both of these receptors are exposed to HRG as described in Sliwkowski et al., J. Biol. Chem., 269 (20): 14661-14665 (1994). Isolated by immunoprecipitation and analyzed by SDS-PAGE.

  “Antibodies” (Abs) and “immunoglobulins” (Igs) are glycoproteins having the same structural characteristics. While antibodies exhibit binding specificity for a particular antigen, immunoglobulins include both antibodies and other antibody-like molecules that lack antigen specificity. The latter type of polypeptide is produced, for example, at low levels by the lymphatic system and at increased levels by myeloma.

“Natural antibodies” and “natural immunoglobulins” are heterotetrameric glycoproteins of approximately 150,000 daltons, usually composed of two identical light (L) chains and two identical heavy (H) chains. Each light chain is linked to the heavy chain by one covalent disulfide bond, and the number of disulfide bonds varies among the heavy chains of different immunoglobulin isotypes. Each heavy and light chain has regularly spaced interchain disulfide bonds. Each heavy chain has at one end followed by a number of constant domains variable domain (V _H). Each light chain has a variable domain (V _L ) at one end and a constant domain at the other end; the light chain constant domain is aligned with the first constant domain of the heavy chain, and the light chain variable domain is the heavy chain Is aligned with the variable domain. Certain amino acid residues are thought to form an interface between the light and heavy chain variable domains.

  The term “variable” refers to the fact that certain sites in the variable domain vary widely in sequence within an antibody and are used for the binding and specificity of each particular antibody to that particular antigen. To do. However, variability is not uniformly distributed across the variable domains of antibodies. It is enriched in three segments called hypervariable regions or complementarity determining regions (CDS) of both the light and heavy chain variable domains. The more highly conserved portions of variable domains are called the framework region (FR). The natural heavy and light chain variable domains primarily take a β-sheet configuration linked by three CDRs that bind the β-sheet structure and in some cases form a loop bond that forms part of it. Each of the FR regions is included. The CDRs of each chain are bound closer to the FR and, together with the CDRs of the other chains, contribute to the formation of the antigen binding site of the antibody (Kabat et al., NIH Publ. No. 91-3242, Vol. I Pp. 647-669 [1991]). The constant domain is not directly related to the binding of the antibody to the antigen, but indicates the involvement of the antibody in various effector functions, such as antibody-dependent cytotoxic activity.

  Upon papain digestion of the antibody, two identical antigen-binding fragments, each called a “Fab” fragment with a single antigen-binding site, and the remaining “Fc” fragment, whose name represents the ability to easily crystallize, Produced. Pepsin treatment yields an F (ab ′) 2 fragment that has two antigen binding sites and can further crosslink antigen.

“Fv” is the minimum antibody fragment which contains a complete antigen recognition and antigen binding site. This region consists of a dimer of one heavy chain and one light chain variable domain in tight, non-covalent association. In this arrangement, the three CDRs of each variable domain interact to form an antigen binding site on the V _H -V _L dimer surface. Collectively, the six CDRs confer antigen binding specificity to the antibody. However, even a single variable domain (or half of an Fv containing only three CDRs specific for the antigen) has a lower affinity than the entire binding site, but has the ability to recognize and bind to the antigen. Have.

The Fab fragment also has the constant domain of the light chain and the first constant region (CH1) of the heavy chain. Fab ′ fragments differ from Fab fragments by the addition of a few residues at the carboxy terminus of the heavy chain CH1 region including one or more cysteines from the antibody hinge region. Fab′-SH is the nomenclature here for Fab ′ in which the cysteine residues of the constant domain carry a free thiol group. F (ab ′) ₂ antibody fragments were produced as pairs of Fab ′ fragments that have hinge cysteines between them. Other chemical bonds of antibody fragments are also known.

  The “light chain” of an antibody (immunoglobulin) from any vertebrate species has two distinct types, called kappa (κ) and lambda (λ), based on the amino acid sequence of its constant domain. One is assigned.

  Depending on the amino acid sequence of the heavy chain constant domain, immunoglobulins can be assigned to different classes. There are five main classes of immunoglobulins: IgA, IgD, IgE, IgG and IgM, some of which are further divided into subclasses (isotypes), eg IgG1, IgG2, IgG3 and IgG4, IgA and IgA2. The heavy chain constant domains that correspond to the different classes of immunoglobulins are called α, δ, ε, γ, and μ, respectively. The subunit structures and three-dimensional structures of different classes of immunoglobulins are well known.

  The term “antibody” is used in the broadest sense, particularly intact monoclonal antibodies, polyclonal antibodies, multispecific antibodies formed from at least two intact antibodies (eg, bispecific antibodies), and the organism in which they are desired. Antibody fragments are included as long as they show activity.

“Antibody fragments” comprise a portion of an intact antibody, preferably the antigen binding or variable region of the intact antibody. Examples of antibody fragments include Fab, Fab ′, F (ab ′) ₂ and Fv fragments; diabodies; linear antibodies (Zapata et al., Polypeptide Eng. 8 (10): 1057-1062 [1995] ); Single chain antibody molecules; and multispecific antibodies formed from antibody fragments.

The term “monoclonal antibody” as used herein refers to an antibody obtained from a population of substantially homogeneous antibodies, ie, the naturally occurring possible mutations in which the individual antibodies comprising the population may be present in small amounts. Identical except for mutations. Monoclonal antibodies are highly specific and are directed against a single antigenic site. Furthermore, each monoclonal antibody is directed against a single determinant on the antigen as compared to a normal (polyclonal) antibody that typically includes different antibodies directed against different determinants (epitopes). In addition to its specificity, monoclonal antibodies are advantageous in that they are synthesized from hybridoma cultures that are not contaminated by other immunoglobulins. The modifier “monoclonal” indicates the character of the antibody as being derived from a substantially homogeneous antibody population, and does not imply that the antibody must be produced in any particular way. For example, monoclonal antibodies used in the present invention can be made by the hybridoma method first disclosed by Kohler et al., Nature 256, 495 (1975), or can be made, for example, by recombinant DNA methods (e.g., U.S. Pat. No. 4,816,567). A “monoclonal antibody” is a phage antibody library using the technique described in, for example, Clackson et al., Nature 352: 624-628 (1991), and Marks et al., J. Mol. Biol. 222: 581-597 (1991). It can also be isolated from
Here, a monoclonal antibody is a portion of the heavy chain and / or light chain that is identical or homologous to the corresponding sequence of an antibody from a particular species or an antibody belonging to a particular antibody class or subclass, and the remainder of the chain. A “chimeric” antibody (immunoglobulin) that is identical or homologous to the corresponding sequence of an antibody from another species or of an antibody belonging to another antibody class or subclass, as well as having the desired biological activity As long as they specifically include fragments of those antibodies (US Pat. No. 4,816,567; Morrison et al., Proc. Natl. Acad. Sci. USA, 81: 6851-6855 [1984]).

“Humanized” forms of non-human (eg, murine) antibodies refer to chimeric immunoglobulins, immunoglobulin chains or fragments thereof (eg, Fv, Fab, Fab ′, F (ab ′) 2 or other antigen-binding sub-antibodies of antibodies). Sequence), which includes a minimal sequence derived from non-human immunoglobulin. For the most part, humanized antibodies are CDRs of a non-human species (donor antibody) in which the complementarity determining region (CDR) of the recipient has the desired specificity, affinity and ability, such as mouse, rat or rabbit. It is a human immunoglobulin (recipient antibody) substituted by the residues of In some cases, Fv framework region residues of the human immunoglobulin are replaced by corresponding non-human residues. Furthermore, humanized antibodies may comprise residues that are found neither in the recipient antibody nor in the imported CDR or framework sequences. These modifications are made to further refine and optimize antibody properties. In general, a humanized antibody has at least one, typically all or almost all CDR regions corresponding to those of a non-human immunoglobulin and all or almost all FR regions of a human immunoglobulin sequence. Contains substantially all of the two variable domains. A humanized antibody optimally comprises at least a portion of an immunoglobulin constant region (Fc), typically that of a human immunoglobulin. For further details see Jones et al., Nature 321, 522-525 (1986); Reichman et al., Nature 332, 323-329 (1988) and Presta, Curr. Op. Struct. Biol. 2, 593-596 (1992). That. Humanized antibodies include primatized (PRIMATIZED ^™ ) antibodies in which the antigen binding region of the antibody is derived from an antibody produced by immunizing a macaque monkey with an antigen of interest.

"Single-chain Fv" or "sFv" antibody fragments those containing V _H and V _L domains of antibody, wherein these domains are present in a single polypeptide chain. Preferably, the Fv polypeptide further comprises a polypeptide linker between the _VH and _VL domains that allows the sFv to form the desired structure for antigen binding. For a review of sFv, see, for example, Plueckthun, The Pharmacology of Monoclonal Antibodies, vol. 113, Rosenburg and Moore, Springer-Verlag, New York, pp. 269-315 (1994).

The term “diabody” refers to a small antibody fragment having two antigen binding sites, where the fragment comprises a heavy chain variable domain (V _H ) linked to a light chain variable domain (V _L ) and the same polypeptide chain. (V _H -V _L ) By using a linker that is too short to allow pairing between two domains on the same chain, the domain is forced to pair with the complementary domain of the other chain, creating two antigen binding sites. Diabodies are described in further detail, for example, in European Patent 404097; WO 93/11161; and Hollinger et al., Proc. Natl. Acad. Sci. USA, 90: 6444-6448 (1993).

  An “isolated” antibody is one that has been identified and separated and / or recovered from a component of the natural environment. Contaminating components in its natural environment are substances that interfere with diagnostic or therapeutic uses for antibodies, including enzymes, hormones and other proteinaceous or non-proteinaceous solutes. In a preferred embodiment, the antibody is (1) 95% or more, most preferably 99% or more by weight of the antibody as measured by the Lowry method, and (2) the N-terminal by using a spinning cup seeker. Or to a degree sufficient to obtain at least 15 residues of the internal amino acid sequence; or (3) uniformity is obtained by SDS-PAGE under non-reducing or reducing conditions using Coomassie blue or preferably silver staining. Until purified. Isolated antibody includes the antibody in situ within recombinant cells since at least one component of the antibody's natural environment will not be present. Ordinarily, however, isolated antibody will be prepared by at least one purification step.

The term “salvage receptor binding epitope” as used herein refers to an Ig molecule (eg, IgG ₁ , IgG ₂ , IgG ₃ or IgG ₄ ) that is responsible for increasing the in vivo serum half-life of an IgG molecule. Refers to the epitope of the Fc region.

  “Treatment” refers to both therapeutic treatment and prophylactic or preventative measures. Those in need of treatment include those already suffering as well as those in which the disease is to be prevented.

  “Mammal” intended for treatment refers to any animal classified as a mammal, including humans, household or farm animals, and zoo, sports or pet animals such as dogs, horses, cats, cows, etc. Means. Preferably the mammal is a human.

  A “disease” is any condition that would benefit from treatment with an anti-ErbB2 antibody. This includes chronic and acute diseases or conditions, including pathological conditions that predispose mammals to the disease in question. Examples of diseases to be treated here include, but are not limited to, benign and malignant tumors; leukemias and lymphoid malignancies; neurons, glia, astrocytes, hypothalamus and other glands, macrophages, Includes epithelial, stromal and split cavity diseases; and inflammation, angiogenesis and immune diseases.

  The term “therapeutically effective amount” is used to refer to an amount that has a growth inhibitory effect. Preferably, a therapeutically effective amount is one that has apoptotic activity or is capable of inducing cell death, preferably death of benign or malignant tumor cells, especially cancer cells. Efficacy can be measured in a conventional manner, depending on the condition being treated. For cancer treatment, efficacy can be measured, for example, by assessing disease progression time (TTP) or determining response rate (RR) (see Examples below).

  The terms “cancer” and “cancerous” refer to or describe the physiological condition in mammals that is typically characterized by unregulated cell growth. Examples of cancer include, but are not limited to, carcinoma, lymphoma, blastoma, sarcoma, and leukemia. More specific examples of such cancers include squamous cell carcinoma, small cell lung cancer, non-small cell lung cancer, gastrointestinal cancer, pancreatic cancer, glioblastoma, cervical cancer, ovarian cancer, liver cancer, bladder cancer Liver cancer, breast cancer, colon cancer, colorectal cancer, endometrial cancer, salivary gland cancer, kidney cancer, liver cancer, prostate cancer, vulvar cancer, thyroid cancer, liver cancer and various types of head and neck cancer included.

The term “cytotoxic agent” as used herein refers to a substance that inhibits or suppresses cell function and / or causes destruction of cells. The term is intended to include radioactive isotopes (eg, I ¹³¹ , I ¹²⁵ , Y ⁹⁰ and Re ¹⁸⁶ ), chemotherapeutic agents, and toxins, such as enzymatically active toxins from bacteria, fungi, plants or animals, or fragments thereof. ing.

A “chemotherapeutic agent” is a chemical compound useful in the treatment of cancer. Examples of chemotherapeutic agents include adriamycin (doxorubicin), epirubicin, 5-fluorouracil (5-FU), cytosine arabinoside (“Ara-C”), cyclophosphamide (CYTOXAN ^™ ), thiotepa, busulfan, taxoid Classes such as paclitaxel (Taxol ^R , Bristol-Myers Squibb Oncology, Princeton, NJ) and docetaxel (Taxotere, Rhone-Poulenc Rorer, Antony, France), methotrexate, cisplatin, vinblastine, phosomycin, , Mitomycin C, mitoxantrone, vincristine, vinorelbine, carboplatin, teniposide, daunomycin, carminomycin, aminopterin, dactinomycin, mitomycin, esperamicins (US Patent No. 4 See No. 75187), melphalan and other related nitrogen mustards. This definition also includes hormonal agents that act to modulate or inhibit hormonal effects on tumors, such as tamoxifen and onapristone.

  Other examples of chemotherapeutic agents include alkyl sulfonates such as improsulfan and piposulfan; aziridines such as benzodopa, carbocon, meturedopa, and uredopa; (altretamine), ethyleneimines and methylamelamines including triethylenemelamine, triethylenephosphoramide, triethylenethiophospharamide and trimethylolomelamine; nitrogen mustards such as chlorambucil, chloronaphazine ), Cholophosphamide, estramustine, mechloretamine, mechloretamine oxide hydrochloride, nobenbitine, phenesterine, prednimustine, toro Trofosfamide, uracil mustard; nitrosureas such as carmustine, chlorozotocin, fotemustine, lomustine, nimustine, ranimustine; antibiotics such as aclacinomysins, suramycin (authramycin), azaserine, cactinomycin, calicheamicin, carabicin, carzinophilin, chromomycin, 6-diazo-5-oxo-L-norleucine, daunorubicin, myco Phenolic acid (mycophenolic acid), nogalamycin, olivomycins, peplomycin, potfiromycin, puromycin, streptonigrin, streptozocin, tubercidin, ubenimec , Zinostatin, zorubicin, gentamicin; folic acid analogs such as denopterin, pteropterin, trimetrexate; purine analogs such as fludarabine, 6-mercaptopurine Pyramidine analogues such as ancitabine, azacitidine, 6-azauridine, carmofur, cytarabine, dideoxyuridine, doxyfluridine, enocitabine, and floxuridine; eg, androgens; calusterone), drostanolone propionate, epithiostanol, mepithiostan, testolactone; anti-adrenal drugs such as aminoglutethimide, mitotane, trilostane; folic acid replenisher (r eplenisher, e.g. frolinic acid; acegraton; aldophosphamide glycoside; aminolevulinic acid; amsacrine; bestrabucil; bisantrene; edatraxate; defofamine; Demecolcine; diaziquone; elfornithine; elliptinium acetate; etoglucid; gallium nitrate; oxyurea; lentinan; lonidamine: mitoguazone; mitoxantrone; Nitracrine; pentostatin; phenname; pirarubicin; podophyllinic acid; 2-ethylhydrazide; procarbazine; PKS®; razoxan; schizophyllan; spi tenuazonic acid; triaziquone; 2,2 ', 2' '-trichlorotriethylamine; urethane; vindesine; dacarbazine; mannomustine; mitoblonitol; mitolactol; pipobroman; Gacytosine; chlorambucil; gencitabine; 6-thioguanine; mercaptopurine; platinum; navelbine; novantron; xeloda; ibandronate; Difluoromethylol nitine (DMFO); retinoic acid; capecitabine; and pharmaceutically acceptable salts, acids or derivatives of those mentioned above.

  Other examples of hormonal agents that act to modulate or inhibit hormonal action on tumors include other antiestrogens such as aromatase, 4-hydroxy, which inhibits raloxifene (Evista), 4 (5) -imidazoles. Tamoxifen, trioxifene, keoxifene, and LY11018; and antiandrogens such as flutamide and nilutamide; and pharmaceutically acceptable salts, acids or derivatives of the above .

As used herein, “growth inhibitory agent” refers to a compound or composition that inhibits the growth of cells, particularly ErbB2 overexpressing cancer cells, either in vitro or in vivo. Thus, a growth inhibitor is one that significantly reduces the percentage of ErbB2 overexpressing cells in the S phase. Examples of growth inhibitory agents include agents that block the progression of the cell division cycle (at locations other than S phase), such as agents that induce G1 arrest and M phase arrest. Traditional phase M blockers include vinca (vincristine and vinblastine), Taxol®, and topo II inhibitors such as doxorubicin, epirubicin, daunorubicin, etoposide, and bleomycin. These agents that stop G1, such as DNA alkylating agents, such as tamoxifen, prednisone, dacarbazine, mechloretamine, cisplatin, methotrexate, 5-fluorouracil, and ara-C overflow into S phase arrest. For further information, see Molecular Basis of Cancer, Mendelsohn and Israel, Chapter 1 (WB Saunders; Philadelphia, 1995), entitled “Cell Division Cycle Regulation, Oncogenes, and Antineoplastics” by Murakami et al. In particular, it can be found on page 13. The 4D5 antibody (and functional equivalents thereof) can also be used for this purpose.
“Doxorubicin” is an anthracycline antibiotic. The official chemical name of doxorubicin is (8S-cis) -10-[(3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranosyl) oxy] -7,8,9,10-tetrahydro- 6,8,11-Trihydroxy-8- (hydroxyacetyl) -1-methoxy-5,12-naphthacenedione.

  The term “cytokine” is a generic term for proteins released from one cell population that act as intercellular mediators on other cells. Examples of such cytokines include lymphokines, monokines, and traditional polypeptide hormones. Cytokines include glycoproteins such as growth hormones such as human growth hormone, N-methionyl human growth hormone, and bovine growth hormone; parathyroid hormone; thyroxine; insulin; proinsulin; relaxin; prorelaxin; follicle stimulating hormone (FSH). Hormones, parathyroid stimulating hormone (TSH), and luteinizing hormone (LH); liver growth factor; fibroblast growth factor; prolactin; placental lactogen; tumor necrosis factor-α and -β; Mueller inhibitor; mouse gonadotropin Related peptides; inhibin; activin; vascular endothelial growth factor; integrin; thrombopoietin (TPO); nerve growth factor such as NGF-β; platelet growth factor; transforming growth factor (TGF) such as TGF-α or TGF-β; Insulin-like growth factors I and II; erythropoi Ettin (EPO); Osteoinductive factor; Interferon like interferon α, β, γ; Colony stimulating factor (CSF) like macrophage CSF (M-CSF); Granulocyte macrophage CSF (GM-CSF) and granulocyte CSF (G-CSF); IL-1, IL-1α, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-11, Interleukins (IL) such as IL-12; tumor necrosis factors such as TNF-α or TNF-β; and other polypeptide factors including LIF and kit ligand (KL). As used herein, the term cytokine includes proteins from natural sources or from recombinant cell culture and biologically active equivalents of native sequence cytokines.

  The term “prodrug” as used in this application is a pharmaceutically active substance that is less cytotoxic to tumor cells than the parent drug and can be enzymatically activated or converted to the more active parent form. The precursor or derivative form of For example, Wilman, `` Prodrugs in Cancer Chemotherapy '', Biochemical Society Transactions, 14, pp.375-382, 615th Meeting Belfast (1986) and Stella et al., `` Prodrugs: A Chemical Approach to Targeted Drug Delivery '', Directed Drug Delivery, Borchardt (Ed.), Pp.247-267, Humana Press (1985). Without limitation, the prodrugs of the present invention include phosphate-containing prodrugs, thiophosphate-containing prodrugs, sulfate-containing prodrugs, peptide-containing prodrugs, D-amino acid modified prodrugs, glycosylated prodrugs, β-lactam-containing Prodrugs, optionally substituted phenoxyacetamide-containing prodrugs or optionally substituted phenylacetamide-containing prodrugs, 5-fluorocytosine and other 5-fluorouridine pros that are convertible to more active and cytotoxic-free drugs Includes drag. Non-limiting examples of cytotoxic agents that can be derivatized to the prodrug form used in the present invention include the chemotherapeutic agents listed above.

  “Solid phase” means a non-aqueous matrix to which the antibodies used in the present invention can adhere. Examples of solid phases encompassed herein include those partially or wholly formed from glass (eg, tempered glass), polysaccharides (eg, agarose), polyacrylamide, polystyrene, polyvinyl alcohol and silicone. Is included. In some embodiments, in some contexts, the solid phase includes the wells of an assay plate; in other embodiments, it is a purification column (eg, an affinity chromatography column). The term also includes a discontinuous solid phase of discrete particles, such as those described in US Pat. No. 4,275,149.

  “Liposomes” are various types of lipids, phospholipids and / or surfactants useful for delivery of drugs (eg, anti-ErbB2 antibodies disclosed herein, and optionally chemotherapeutic agents) to mammals. Is an endoplasmic reticulum. The components of the liposome are usually arranged in a bilayer structure similar to the lipid arrangement of a biofilm.

  The term “package insert” is intended to mean instructions that are usually included in a commercial package of therapeutic products, including information about efficacy, usage, dosage, method of administration, contraindications and / or warnings regarding the use of such therapeutic products used.

II. Production of anti-ErbB2 antibodies Exemplary techniques for producing the antibodies used in the present invention are described below. The ErbB2 antigen used to produce the antibody may be, for example, the extracellular domain of ErbB2 containing the desired epitope or a soluble form of some of them. Alternatively, to produce antibodies, cells expressing ErbB2 on their cell surface (eg, NIH-3T3 cells transformed to overexpress ErbB2; or carcinoma cell lines such as SKBR3 cells, Stancovski et al., PNAS (USA) 88: 8691-8695 [1991]) can also be used. Other forms of ErbB2 useful for the production of antibodies will be apparent to those skilled in the art.

(i) Polyclonal antibodies Polyclonal antibodies are preferably raised in animals by multiple subcutaneous (sc) or intraperitoneal (ip) injections of the relevant antigen and an adjuvant. A protein that is immunogenic in the species to be immunized, such as keyhole limpet hemocyanin, serum albumin, bovine thyroglobulin, or soy trypsin inhibitor, and a bifunctional or derivatizing agent such as maleimidobenzoylsulfosuccinimide ester ( Conjugated by cysteine residue), N-hydroxysuccinimide (by lysine residue), glutaraldehyde, succinic anhydride, SOCl ₂ , or R ¹ and R ¹ are different alkyl groups R ¹ N═C═NR It is useful.

  The animal is combined with 3 volumes of complete Freund's adjuvant, eg, 100 μg or 5 μg of protein or conjugate (for rabbits or mice, respectively), and the solution is injected intradermally at multiple sites to produce antigens, immunogenic conjugates, or Immunize against the derivative. One month later, the animals are boosted by subcutaneous injection at multiple sites with an initial amount of 1/5 to 1/10 peptide or conjugate in complete Freund's adjuvant. After 7 to 14 days, animals are bled and the serum is assayed for antibody titer. Animals are boosted until the titer reaches a plateau. Preferably, the animal is boosted with a conjugate of the same antigen but conjugated to a different protein and / or conjugated with a different cross-linking agent. Conjugates can also be prepared in recombinant cell culture as protein fusions. In addition, an aggregating agent such as alum is preferably used to enhance the immune response.

(ii) Monoclonal antibody Monoclonal antibody means an antibody obtained from a substantially homogeneous population of antibodies, ie, the individual antibodies that make up the population are identical except for possible naturally occurring mutations that may be present in small amounts. It is. Thus, the modifier “monoclonal” indicates the character of the antibody, not a mixture of separate antibodies.
For example, monoclonal antibodies can be made using the hybridoma method first described by Kohler et al., Nature, 256: 495 (1975), or can be made by recombinant DNA methods (US Pat. No. 4,816,567).

  In the hybridoma method, mice or other suitable host animals, such as hamsters, are immunized as described above, and lymphocytes that produce or can produce antibodies that specifically bind to the proteins used for immunization. To derive. Alternatively, lymphocytes can be immunized in vitro. The lymphocytes are then fused with myeloma cells using a suitable flux such as polyethylene glycol to form hybridoma cells (Goding, Monoclonal Antibodies: Principles and Practice, pages 590-103 [Academic Press, 1986 ]).

  The hybridoma cells thus prepared are seeded and grown in a suitable medium that preferably contains one or more substances that inhibit the growth or survival of the unfused parent myeloma cells. For example, if the parent myeloma cells lack the enzyme hypoxanthine anidine phosphoribosyltransferase (HGPRT or HPRT), the medium for the hybridoma is typically a substance that prevents the growth of HGPRT-deficient cells. It will contain hypoxanthine, aminopterin and thymidine (HAT medium).

  Preferred myeloma cells are those that fuse efficiently, support stable high level production of antibodies by selected antibody-producing cells, and are sensitive to a medium such as HAT medium. Among these, preferred myeloma cell lines are the mouse myeloma lineage, such as the MOPC-21 and MPC-11 mouse tumors available from the Soak Institute Cell Distribution Center, San Diego, California, USA, and It was derived from SP-2 or X63-Ag8-653 cells available from American Type Culture Collection, Rockville, Maryland, USA. Human myeloma and mouse-human heteromyeloma cell lines have also been disclosed for the production of human monoclonal antibodies (Kozbor, J. Immunol., 133: 3001 (1984); Brodeur et al., Monoclonal Antibody Production Techniques and Applications 51-63 [Marcel Dekker, Inc., New York, 1987]).

Culture medium in which hybridoma cells are growing is assayed for production of monoclonal antibodies directed against the antigen. Preferably, the binding specificity of monoclonal antibodies produced by hybridoma cells is measured by immunoprecipitation or in vitro binding assays, such as radioimmunoassay (RIA) or enzyme-linked immunosorbent assay (ELISA).
The binding affinity of a monoclonal antibody can be measured, for example, by the Scatchard analysis method of Munson et al., Anal. Biochem., 107: 220 (1980).

  Once hybridoma cells producing antibodies of the desired specificity, affinity, and / or activity are identified, the clones can be subcloned by limiting dilution and grown by standard methods (Goding, Monoclonal Antibodies : Principles and Practice, pp. 59-103 [Academic Press, 1986]). Suitable culture media for this purpose include, for example, D-MEM or RPMI-1640 medium. In addition, the hybridoma cells can be grown in vivo as ascites tumors in animals.

  Monoclonal antibodies secreted by subclones are obtained from medium, ascites fluid, or serum by conventional immunoglobulin purification methods such as protein A-sepharose, hydroxyapatite chromatography, gel electrophoresis, dialysis, or affinity chromatography. It is preferably separated.

  The DNA encoding the monoclonal antibody is immediately isolated and sequenced using conventional methods (eg, by using oligonucleotide probes that can specifically bind to the genes encoding mouse heavy and light chains). It is determined. Hybridoma cells are a preferred source of such DNA. Once isolated, the DNA is placed in an expression vector which is then put into an E. coli cell, monkey COS cell, Chinese hamster ovary (CHO) cell, or myeloma cell that otherwise does not produce immunoglobulin protein. It can be transfected into host cells to achieve the synthesis of monoclonal antibodies in recombinant host cells. Review articles on recombinant expression in bacteria of DNA encoding the antibody include Skerra et al., Curr. Opinion in Immunol., 5: 256-262 (1993) and Plueckthum, Immunol. Revs., 130: 151-188. (1992).

  In a further embodiment, antibodies or antibody fragments can be isolated from antibody phage libraries produced using the techniques described in McCafferty et al., Nature, 348: 552-554 (1990). Clackson et al., Nature, 352: 624-628 (1991) and Marks et al., J. Mol. Biol., 222: 581-597 (1991) describe the separation of mouse and human antibodies using a phage library. . Subsequent publications show the production of high affinity (nM range) human antibodies by chain mixing (Marks et al., Bio / Technology, 10: 779-783 [1992]), as well as strategies for constructing very large phage libraries. As described combinatorial infection and in vivo recombination (Waterhouse et al., Nuc. Acids. Res., 21: 2265-2266 [1993]). These techniques are therefore viable alternatives to traditional monoclonal antibody hybridoma methods for the separation of monoclonal antibodies.

  DNA can also be obtained, for example, by replacing coding sequences for human heavy and light chain constant domains in place of homologous mouse sequences (US Pat. No. 4,816,567; Morrison et al., Proc. Nat. Acad. Sci., USA, 81: 6851 [1984]), or by covalently linking all or part of the coding sequence of the non-immunoglobulin polypeptide to the immunoglobulin coding sequence.

  Typically, such a non-immunoglobulin polypeptide is substituted with a constant domain of an antibody, or substituted with the variable domain of one antigen binding site of an antibody, so that one antigen binding site has specificity for an antigen. And another antigen binding site with specificity for a different antigen is produced.

(iii) Humanized or human antibodies Methods for humanizing non-human antibodies are well known in the art. Preferably, one or more amino acid residues derived from non-human are introduced into the humanized antibody. These non-human amino acid residues are often referred to as “import” residues, which are typically taken from an “import” variable domain. Humanization is essentially the method of Winter and co-workers (Jones et al., Nature, 321: 522-525 (1986), by replacing the corresponding sequence of a human antibody with a rodent CDR or CDR sequence. Riechmann et al., Nature, 332: 323-327 (1988), Verhoeyen et al., Science, 239: 1534-1536 [1988]). Thus, such “humanized” antibodies are chimeric antibodies (US Pat. No. 4,816,567) wherein substantially less than an intact human variable domain has been substituted with the corresponding sequence from a non-human species. In practice, humanized antibodies are typically human antibodies in which some CDR residues and possibly some FR residues are substituted by residues from analogous sites in rodent antibodies.

  To reduce antigenicity, the selection of both human light and heavy variable domains for use in generating humanized antibodies is very important. In the “best fit method”, the sequence of the variable domain of a rodent antibody is screened against the entire library of known human variable domain sequences. The human sequence closest to that of the rodent is then accepted as the human framework region (FR) of the humanized antibody (Sims et al., J. Immunol., 151: 2296 (1993); Chothia et al., J. Mol. Biol ., 196: 901 [1987]). Another method uses a particular framework region derived from the consensus sequence of all human antibodies of a particular subgroup of light or heavy chains. The same framework can be used for several different humanized antibodies (Carter et al., Proc. Natl. Acad. Sci. USA, 89: 4285 (1992); Presta et al., J. Immunol., 151: 2623 [1993]) .

  It is further important that antibodies be humanized with retention of high affinity for the antigen and other favorable biological properties. To achieve this goal, a preferred method uses a three-dimensional model of the parent and humanized sequences to prepare the humanized antibody through an analysis step of the parent sequence and various conceptual humanized products. Three-dimensional immunoglobulin models are commonly available and are familiar to those skilled in the art. Computer programs that illustrate and display putative three-dimensional conformational structures of selected candidate immunoglobulin sequences are commercially available. Viewing these representations allows analysis of the likely role of residues in the function of the candidate immunoglobulin sequence, ie, analysis of residues that affect the ability of the candidate immunoglobulin to bind antigen. In this way, FR residues can be selected and combined from the recipient and import sequences so that the desired antibody characteristic, such as increased affinity for the target antigen (s), is achieved. In general, the CDR residues directly and most substantially affect antigen binding.

Alternatively, it is now possible to create transgenic animals (eg, mice) that can be produced by immunizing the entire repertoire of human antibodies without endogenous immunoglobulin production. For example, it has been described that homozygous removal of the antibody heavy chain joining region (J _H ) gene in chimeric and germ-line mutant mice results in complete inhibition of endogenous antibody production. Transfer of human germline immunoglobulin gene sequences in such germline mutant mice results in the production of human antibodies upon challenge. See Jakobovits et al., Proc. Natl. Acad. Sci. USA, 90: 2551 (1993); Jakobovits et al., Nature 362: 255-258 (1993); Bruggerman et al., Year in Immuno., 7:33 (1993). I want. Human antibodies can also be removed from phage display libraries (Hoogenboom et al., J. Mol. Biol., 227: 381 (1991); Marks et al., J. Mol. Biol. 222: 581-597 [1991]).

(iv) Antibody fragments Various techniques have been developed to produce antibody fragments. Traditionally, these fragments were derived through proteolytic digestion of intact antibodies (e.g. Morimoto et al., Journal of Biochemical and Biophysical Methods 24: 107-117 (1992) and Brennan et al., Science, 229: 81 [1985]. However, these fragments can now be produced directly by recombinant host cells. For example, antibody fragments can be isolated from the antibody phage libraries discussed above. Alternatively, Fab′-SH fragments can be recovered directly from E. coli and chemically combined to form F (ab ′) ₂ fragments (Carter et al., Bio / Technology 10: 163-167 [1992]). In another approach, F (ab ′) fragments can be isolated directly from recombinant host cell culture. Other methods for the production of antibody fragments will be apparent to those skilled in the art. In other embodiments, the selection antibody is a single chain Fv fragment (scFV). See WO 93/16185.

(v) Bispecific antibodies Bispecific antibodies are antibodies that have binding specificities for at least two different epitopes. Exemplary bispecific antibodies can bind to two different epitopes of the ErbB2 protein. For example, one arm can bind to an ErbB2 domain 1 epitope, such as a 7C2 / 7F3 epitope, and the other can bind to a different ErbB2 epitope, such as a 4D5 epitope. In other such antibodies, a binding site for EGFR, ErbB3 and / or ErbB4 can bind to an ErbB2 binding site. Alternatively, the anti-ErbB2 arm may be an Fc receptor for IgG (FcγR), such as FcγRI (CD64), FcγRII (CD32) and FcγRIII (CD16), or a T cell receptor molecule ( For example, it can bind to an arm that binds to a trigger molecule on leukocytes such as CD2 or CD3). Bispecific antibodies can also be used to localize cytotoxic agents to cells expressing ErbB2. These antibodies have an ErbB2 binding arm and an arm that binds a cytotoxic agent (eg, saporin, anti-interferon-α, vinca alkaloid, ricin A chain, methotrexate or radioisotope hapten). Bispecific antibodies can be prepared as full length antibodies or antibody fragments (eg F (ab ′) ₂ bispecific antibodies).

  Methods for making bispecific antibodies are known in the art. Traditional production of full-length bispecific antibodies is based on the co-expression of two immunoglobulin heavy chain-light chain pairs, where the two chains have different specificities (Millstein et al., Nature, 305: 537 -539 [1983]). Because of the random selection of immunoglobulin heavy and light chains, these hybridomas (four-part hybrids) produce a possible mixture of 10 different antibody molecules, only one of which is the correct bispecific structure. Have Usually, the purification of the correct molecule performed by the affinity chromatography step is quite cumbersome and the product yield is low. Similar methods are disclosed in WO 93/08829 and Traunecker et al., EMBO J. 10: 3655-3659 [1991].

  In a different approach, antibody variable domains with the desired binding specificities (antigen-antibody combining sites) are fused to immunoglobulin constant domain sequences. The fusion is preferably a fusion with an immunoglobulin heavy chain constant domain comprising at least part of the hinge, CH2 and CH3 regions. It is desirable to have a first heavy chain constant region (CH1) containing the site necessary for light chain binding, present in at least one of the fusions. DNA encoding an immunoglobulin heavy chain fusion, if desired, an immunoglobulin light chain, is inserted into a separate expression vector and cotransfected into a suitable host organism. This provides great flexibility in adjusting the mutual proportions of the three polypeptide fragments in an embodiment where unequal proportions of the three polypeptide chains used in the assembly result in optimal yields. However, when expression at an equal ratio of at least two polypeptide chains yields a high yield, or when the ratio is not particularly important, the coding sequence for all two or three polypeptide chains Can be inserted into one expression vector.

  In a preferred embodiment of this approach, the bispecific antibody comprises a hybrid immunoglobulin heavy chain of one arm having a first binding specificity and a hybrid immunoglobulin heavy chain-light chain pair (first antibody) of the other arm. Providing a second binding specificity). This asymmetric structure separates the desired bispecific compound from unwanted immunoglobulin chain combinations, since only half of the bispecific molecule has an immunoglobulin light chain, providing an easy separation method. It turns out that it makes it easier. This approach is disclosed in WO 94/04690. For further details of generating bispecific antibodies see, for example, Suresh et al., Methods in Enzymology, 121: 210 (1986).

According to another approach described in WO 96/27011, the interface between a pair of antibody molecules can be manipulated to maximize the percentage of heterodimers recovered from recombinant cell culture. A suitable interface includes at least a portion of the C _H 3 domain of an antibody constant domain. In this method, one or more small amino acid side chains from the interface of the first antibody molecule are replaced with larger side chains (eg tyrosine or tryptophan). A complementary “cavity” of the same or similar size as the large side chain is created at the interface of the second antibody molecule by replacing the large amino acid side chain with a small one (eg, alanine or threonine). This provides a mechanism to increase the yield of heterodimers over other unwanted end products such as homodimers.

  Bispecific antibodies also include cross-linked or “heteroconjugate” antibodies. For example, one of the heteroconjugate antibodies can be bound to avidin and the other bound to biotin. Such antibodies have been proposed, for example, to target immune system cells against unwanted cells (US Pat. No. 4,676,980) and for the treatment of HIV infection (WO 91/00360, 92/00373). And European Patent No. 03089). Heteroconjugate antibodies can be made using any convenient cross-linking method. Suitable crosslinkers are well known in the art and are disclosed in US Pat. No. 4,676,980, along with several crosslinking techniques.

Techniques for producing bispecific antibodies from antibody fragments have also been described in the literature. For example, bispecific antibodies can be prepared using chemical linkage. Brennan et al., Science, 229: 81 (1985) describes a procedure in which intact antibodies are proteolytically cleaved to produce F (ab ′) ₂ fragments. These fragments are reduced in the presence of the dithiol complexing agent sodium arsenite to stabilize vicinal dithiols and prevent intermolecular disulfide formation. The produced Fab ′ fragment is then converted to a thionitrobenzoate (TNB) derivative. One of the Fab′-TNB derivatives is then reconverted to Fab′-thiol by reduction with mercaptoethylamine and mixed with an equimolar amount of the other Fab′-TNB derivative to form a bispecific antibody. The produced bispecific antibody can be used as a drug for selective immobilization of an enzyme.

Recent progress has facilitated the direct recovery of Fab′-SH fragments from E. coli, which can be chemically coupled to form bispecific antibodies. Shalaby et al., J.Exp.Med, 175:. 217-225 ( 1992) , describes the production of a fully humanized bispecific antibody F (ab ') ₂ molecule. Each Fab ′ fragment is secreted separately from E. coli and undergoes directed chemical coupling in vitro to form bispecific antibodies. The bispecific antibody thus formed is capable of binding to normal human T cells and cells overexpressing ErbB2 receptor, and triggers cytolytic activity of human cytotoxic lymphocytes against human breast tumor targets. Become.

Various methods for making and isolating bispecific antibody fragments directly from recombinant cell culture have also been described. For example, bispecific antibodies have been produced using leucine zippers. Kostelny et al., J. Immunol. 148 (5): 1547-1553 (1992). Leucine zipper peptides from Fos and Jun proteins are linked to the Fab ′ portions of two different antibodies by gene fusion. Antibody homodimers are reduced at the hinge region to form monomers and then reoxidized to form antibody heterodimers. This method can also be used for the production of antibody homodimers. The “diabody” technique described by Hollinger et al., Proc. Natl. Acad. Sci. USA, 90: 6444-6448 (1993) provided an alternative mechanism for generating bispecific antibody fragments. A fragment consists of a heavy chain variable domain (V _H ) linked to a light chain variable domain (V _L ) by a linker that is short enough to allow pairing between two domains on the same chain. Therefore, V _H and V _L domains of one fragment are forced to pair with the complementary V _L and V _H domains of another fragment, forming two antigen-binding sites. Other strategies for producing bispecific antibody fragments by use of single chain Fv (sFv) dimers have also been reported. See Gruber et al., J. Immunol. 152: 5368 (1994).
More than bivalent antibodies are also contemplated. For example, trispecific antibodies can be prepared. Tutt et al. J. Immunol. 147: 60 (1991).

(vi) Screening for antibodies with the desired properties Techniques for producing antibodies have been described above. An antibody having the characteristics described herein is selected.
In order to select antibodies that induce cell death, the degree of loss of membrane integrity as determined by, for example, PI, trypan blue or 7AAD incorporation is determined relative to controls. A preferred assay is the “PI uptake assay using BT474 cells”. In this assay, BT474 cells (American Type Culture Collection [Rockville, MD]) were treated with Dulbecco's Modified Eagle Medium (D-MEM); 10% heat-inactivated FBS (Hyclone) and 2 mM L-glutamine. In ham F-12 supplemented with 50 (50:50). (Thus, the assay is performed in the absence of complement and immune effector cells). BT474 cells are seeded in 100 × 20 mm dishes at a density of 3 × 10 ⁶ per dish and allowed to attach overnight. The medium is then removed and replaced with fresh medium alone or with medium containing 10 μg / ml of the appropriate MAb. Incubate cells for 3 days. Following each treatment, the monolayer is washed with PBS and separated by trypsinization. The cells were then centrifuged at 1200 rpm for 5 minutes at 4 ° C. and the pellet was resuspended in 3 ml of Ca ⁺ binding ice cold buffer (10 mM Hepes, pH 7.4, 140 mM NaCl, 2.5 mM CaCl ₂ ). And aliquot into 35 mm strainer-capped 12 × 75 tubes (1 ml per tube, 3 tubes per treatment group) for cell clump removal. Samples are analyzed using a FACSCAN ^™ flow cytometer and FACSCONVERT ^™ CellQuest software (Becton Dickinson). An antibody is selected that induces a statistically significant level of cell death, as measured by PI uptake.

To select an antibody that induces apoptosis, an annexin binding assay using BT474 cells can be used. BT474 cells are cultured and seeded in dishes as described in the previous paragraph. The medium is then collected and replaced with fresh medium alone or with medium containing 10 μg / ml of the appropriate MAb. After incubating for 3 days, the monolayer is washed with PBS and separated by trypsinization. The cells are then centrifuged, resuspended in Ca ⁺ coupled ice-cold buffer, and aliquoted into tubes as described above for the cell death assay. A labeled annexin (eg, annexin V-FTIC) (1 μg / ml) is then placed in the tube. Samples are analyzed using a FACSCAN ^™ flow cytometer and FACSCONVERT ^™ CellQuest software (Becton Dickinson). An antibody that induces a statistically significant level of annexin binding relative to a control is selected as an apoptosis-inducing antibody.

In addition to the annexin binding assay, a “DNA staining assay using BT474 cells” is available. To perform this assay, BT474 cells treated with the antibody of interest as described in the previous two paragraphs were incubated with 9 μg / ml HOECHST33342 ^™ for 2 hours at 37 ° C. and then MODFILT ^™ software ( Verity Software House) and analyzed with an EPICS ELITE ^™ flow cytometer (Coulter Corporation). Using this assay, an antibody that induces a change in the percentage of apoptotic cells that is 2-fold or more (preferably more than 3-fold) over untreated cells (up to 100% apoptotic cells) is selected as a pro-apoptotic antibody. The

  To screen for antibodies that bind to an epitope on ErbB2 bound by an antibody of interest, conventional cross-blocking as described in Antibodies, A Laboratory Manual, Cold Spring Harbor Laboratory, Harlow and David Lane (1988). An assay can be performed. Alternatively, epitope mapping can be performed by a conventionally known method.

To identify anti-ErbB2 antibodies that inhibit SKBR3 cell growth by 50-100% in cell culture, the SKBR3 assay described in WO 89/06692 can be performed. According to this assay, SKBR3 cells are grown in a 1: 1 mixture of DMEM and F12 medium supplemented with 10% fetal calf serum, glutamine and penicillin streptomycin. SKBR3 cells are seeded at 20000 cells in a 35 mm cell culture dish (2 ml / 35 mm dish). Add 2.5 μg / ml anti-ErbB2 antibody per dish. After 6 days, the number of cells compared to untreated cells is counted using an electronic COULTER ^™ cell counter. Antibodies that inhibit SKBR3 cell growth by 50-100% are selected for combination with the apoptotic antibodies described above.

(vii) Design of effector function It is desirable to modify the antibody of the present invention for effector function, for example, to enhance the efficacy of the antibody in the treatment of cancer. For example, cysteine residues are introduced into the Fc region to allow the formation of interchain disulfide bonds in this region. The homodimeric antibody produced in this way may have improved internalization ability and / or increased complement-mediated cell killing and antibody-dependent cellular cytotoxicity (ADCC). See Caron et al., J. Exp. Med. 176: 1191-1195 (1992) and Shopes, BJImmunol. 148: 2918-2922 (1992). Homodimeric antibodies with enhanced anti-tumor activity can also be prepared using heterobifunctional cross-linking agents as described in Wolff et al., Cancer Research 53: 2560-2565 (1993). Alternatively, an antibody can be designed that has a dual Fc region and thus may have enhanced complement lysis and ADCC ability. See Stevenson et al., Anti-cancer Drug Design 3: 219-230 (1989).

(viii) Immunoconjugates The invention is also described herein and includes cytotoxic agents such as chemotherapeutic agents, toxins (eg, enzymatically active toxins or fragments thereof from bacteria, fungi, plants or animals), or radioactive isotopes ( That is, the present invention relates to an immunoconjugate containing an antibody conjugated to a radioconjugate).

Chemotherapeutic agents useful for the production of such immunoconjugates are described above. Usable enzyme active toxins and fragments thereof include diphtheria A chain, non-binding active fragment of diphtheria toxin, exotoxin A chain (Pseudomonas aeruginosa), ricin A chain, abrin A chain, modeccin ) A chain, alpha-sarcin, Aleurites fordii protein, dianthin protein, Phytolaca americana protein (PAPI, PAPII and PAP-S), momordica momordica Included are charantia inhibitors, curcin, crotin, sapaonaria officinalis inhibitors, gelonin, mitogellin, restrictocin, phenomycin, enomycin and trichothecenes. A variety of radionuclides are also available for the production of radioconjugated anti-ErbB2 antibodies. Specific examples include ²¹² Bi, ¹³¹ I, ¹³¹ In, ⁹⁰ Y, and ¹⁸⁶ Re.

  Conjugates of antibodies and cytotoxic agents have various bifunctional protein coupling agents such as N-succinimidyl-3- (2-pyridylthiol) propionate (SPDP), iminothiolane (IT), imidoesters bifunctional Derivatives (e.g. dimethyl adipimidate HCL), active esters (e.g. disuccinimidyl suberate), aldehydes (e.g. glutaraldehyde), bisazide compounds (e.g. bis (p-azidobenzoyl) hexanediamine), Bis-diazonium derivatives (eg bis- (p-diazoniumbenzoyl) ethylenediamine), diisocyanates (eg triene-2,6-diisocyanate), and diactive fluorine compounds (eg 1,5-difluoro-2,4-diisocyanate) Nitrobenzene) can be used. For example, a ricin immunotoxin can be prepared as described in Vitetta et al., Science 238: 1098 (1987). Carbon-14 labeled 1-isothiocyanatobenzyl-3-methyldiethylene-triaminepentaacetic acid (MX-DTPA) is an example of a chelating agent for conjugating radionucleotide to an antibody. See WO94 / 11026.

  In other embodiments, the antibody is conjugated to a “receptor” (eg, streptavidin) for use in tumor pre-targeting. Here an antibody-receptor conjugate is administered to a patient, followed by a chelating agent to remove unbound conjugate from the circulation and a “ligand” (eg, avidin) that is conjugated to a cytotoxic agent (eg, a radionucleotide). Is administered.

(ix) Immunoliposomes The anti-ErbB2 antibodies disclosed herein can also be formulated as immunoliposomes. Liposomes containing antibodies are described, for example, in Epstein et al., Proc. Natl. Acad. Sci. USA 82: 3688 (1985); Hwang et al., Proc. Natl. Acad. Sci. USA 77: 4030 (1980); Prepared by methods known in the art as described in US Pat. Nos. 4,485,045 and 4,544,545. Liposomes with increased circulation time are disclosed in US Pat. No. 5,013,556.

  Particularly useful liposomes can be made by the reverse phase evaporation method with a lipid composition containing phosphatidylcholine, cholesterol and PEG-derivatized phosphatidylethanolamine (PEG-PE). Liposomes are extruded through a filter with a defined pore size to obtain liposomes having a desired diameter. Fab ′ fragments of the antibodies of the invention can be conjugated to liposomes via a disulfide exchange reaction as described in Martin et al., J. Biol. Chem. 257: 286-288 (1982). . In some cases, the chemotherapeutic agent is included within the liposome. See Gabizon et al., J. National Cancer Inst. 81 (19) 1484 (1989).

(x) Antibody-dependent enzyme-mediated prodrug therapy (ADEPT)
The antibodies of the present invention may also be used in ADEPT by conjugating the antibody to a prodrug activating enzyme that converts a prodrug (eg, a peptidyl chemotherapeutic agent, see WO81 / 01145) to an active anticancer agent. can do. See, for example, WO 88/07378 and US Pat. No. 4,975,278.
The enzyme component of the immunoconjugate useful for ADEPT includes any enzyme that can act on the prodrug to convert it to a more active cytotoxic form.

  Without limitation, enzymes useful in the methods of this invention include alkaline phosphatases useful for converting phosphate-containing prodrugs to free drugs; useful for converting sulfate-containing prodrugs to free drugs Arylsulfatases; cytosine deaminases useful for converting non-toxic 5-fluorocytosine to the anticancer agent 5-fluorouracil; proteases such as serratia protease, thermolysin, subtilisin, carboxypeptidase and cathepsins (eg cathepsins B and L), peptides Useful for converting containing prodrugs to free drugs; D-alanyl carboxypeptidases useful for converting prodrugs containing D-amino acid substituents; free carbohydrate-cleaving enzymes such as glycosylated prodrugs Drug Neuraminidase and β-galactosidase useful for conversion; β-lactamase useful for converting β-lactam derivatized drugs to free drugs; and penicillin amidases, such as their amines with phenoxyacetyl or phenylacetyl groups, respectively Penicillin V amidase or penicillin G amidase useful for converting drugs derivatized in reactive nitrogen to free drugs is included. Alternatively, antibodies having enzymatic activity, also known as “abzymes”, can be used to convert the prodrugs of the invention into free active agents (eg, Massey, Nature 328: 457-458 [1987 ]). Antibody-abzyme conjugates can be prepared to deliver the abzyme to a tumor cell population as described herein.

  The enzymes of this invention can be covalently bound to anti-ErbB2 antibodies by using techniques well known in the art, such as the heterobifunctional cross-linking reagents discussed above. Alternatively, a fusion protein in which at least the binding region of the antibody of the present invention is bound to at least a functionally active site of the enzyme of the present invention is prepared using recombinant DNA technology well known in the art. (Neuberger et al., Nature 312: 604-608 [1984]).

(xi) Antibody-salvage receptor binding epitope fusion In certain embodiments of the invention, it may be desirable to use an antibody fragment rather than an intact antibody, eg, to increase tumor penetration. In this case, it is desirable to modify the antibody fragment in order to increase its serum half-life. This can be accomplished, for example, by introducing a salvage receptor binding epitope into the antibody fragment (eg, by mutation of an appropriate region in the antibody fragment, or then at either end or center of the antibody fragment, eg, DNA or peptide synthesis. By introducing an epitope into the peptide tag fused by

  A systematic method for preparing such antibody variants with increased in vivo half-life comprises several steps. The first involves identifying the sequence and conformation of the salvage receptor binding epitope of the Fc region of an IgG molecule. Once this epitope is identified, the sequence of the antibody of interest is modified to include the sequence and conformation of the identified binding epitope. After mutating the sequence, the antibody variant is examined to see if it has a longer in vivo half-life than the original antibody. For testing, if the antibody variant does not have a longer in vivo half-life, its sequence is further modified to include the sequence and conformation of the identified binding epitope. The modified antibody is tested for increased in vivo half-life and this process continues until a molecule is obtained that exhibits a longer in vivo half-life.

  The salvage receptor binding epitope thus introduced into the antibody of interest is any suitable epitope as described above, the nature of which depends, for example, on the type of antibody being modified. Metastasis is made such that the antibody of interest has the biological activity described herein.

The epitope preferably constitutes a region where one or more amino acid residues from one or two loops of the Fc domain are transferred to similar positions in an antibody fragment. Even more preferably, three or more residues of one or two loops of the Fc domain are transferred. More preferably, the epitope is taken from the CH2 domain of the Fc region (eg of IgG) and transferred to the CH1, CH3, or _VH region of the antibody, or one or more such regions. Alternatively, the epitope is taken from the CH2 domain of the Fc region, _{C L} region or _{V L} region of an antibody fragment, or transferred to both.

In one most preferred embodiment, the salvage receptor binding epitope comprises the sequence (5 ′ to 3 ′): PKNSSSMISNTP (SEQ ID NO: 3), optionally HQSLGTQ (SEQ ID NO: 4), HQNLSDGGK (SEQ ID NO: 4). 5), HQNISDKK (SEQ ID NO: 6), or VISSHLGQ (SEQ ID NO: 7), further comprising a antibody fragment, particularly where the antibody fragment is Fab or F (ab ′) ₂ . In other most preferred embodiments, the salvage receptor binding epitope comprises the sequence (5 ′ to 3 ′): HQNLSDGK (SEQ ID NO: 5), HQNISDGK (SEQ ID NO: 6), or VISSHLGQ (SEQ ID NO: 7) and the sequence : A polypeptide containing PKNSSSMISNTP (SEQ ID NO: 3).

(ix) Purification of anti-ErbB2 antibody When using recombinant techniques, the antibody can be produced intracellularly, in the periplasmic space, or directly secreted into the medium. When antibodies are produced intracellularly, as a first step, particulate debris, whether host cells or lysed fragments, is removed, for example, by centrifugation or ultrafiltration. Carter et al., Bio / Technology 10 : 163-167 (1992) describes a procedure for isolating antibodies secreted into the periplasmic space of E. coli. Briefly, the cell paste is dissolved over about 30 minutes in the presence of sodium acetate (pH 3.5), EDTA, and phenylmethylsulfonyl fluoride (PMSF). Cell debris can be removed by centrifugation. If the antibody is secreted into the medium, the supernatant from such an expression system is preferably first concentrated using a commercially available protein concentration filter, such as an Amicon or Milliporepericon ultrafiltration unit. The Protease inhibitors such as PMSF may be included in any of the previous steps to inhibit proteolysis and antibiotics may be included to prevent the growth of foreign contaminants.

Antibody compositions prepared from cells can be purified using, for example, hydroxylapatite chromatography, gel electrophoresis, dialysis, and affinity chromatography, with affinity chromatography being a preferred purification method. The suitability of protein A as an affinity ligand depends on the species and isotype of any immunoglobulin Fc domain that is present in the antibody. Protein A can be used to purify antibodies based on human γ1, γ2, or γ4 heavy chains (Lindmark et al., J. Immunol. Meth. 62: 1-13 [1983]). Protein G is recommended for all mouse isotypes and human γ3 (Guss et al., EMBO J. 5: 1567-1575 [1986]). The matrix to which the affinity ligand is attached is most often agarose, but other matrices can be used. The use of a mechanically stable matrix such as calibrated glass or poly (styrenedivinyl) benzene allows for faster flow rates and shorter processing times than agarose. If the antibody contains a C _H 3 domain, Bakerbond ABX ^™ resin (JT Baker, Philipsburg, NJ) is useful for purification. Fractionation on an ion-exchange column, ethanol precipitation, Reverse Phase HPLC, silica by chromatography heparin sepharose (SEPHAROSE ^TM) by chromatography, chromatography on an anion or cation exchange resin (such as a polyaspartic acid column), chromatofocusing, Other protein purification techniques such as SDS-PAGE and ammonium sulfate precipitation are also available depending on the antibody to be recovered.

  Following the previous purification step, the mixture containing the antibody of interest and contaminants is preferably eluted with an elution buffer at a pH of about 2.5-4.5, preferably at a low salinity (eg, about 0-0). .25M salt) may be subjected to low pH hydrophobic interaction chromatography.

III. Pharmaceutical preparations The therapeutic preparations of antibodies used in the present invention may be in the form of lyophilized preparations or aqueous solutions, with any pharmaceutically acceptable carrier, excipient or stabilizer and the desired degree of purification. Prepared and stored (Remington's Pharmaceutical Sciences, 16th edition, A. Osol, Ed., [1980]). Acceptable carriers, excipients or stabilizers are nontoxic to recipients at the dosages and concentrations used, and include buffers such as phosphate, citrate and other organic acids; anticorrosives including ascorbic acid and methionine. Preservatives (octadecyldimethylbenzylammonium chloride; hexamethonium chloride; benzalkonium chloride; benzethonium chloride; phenol, butyl or benzyl alcohol; alkyl parabens such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol; 3 -Pentanol; and m-cresol); low molecular weight (less than 10 residues) polypeptide; protein such as serum albumin, gelatin or immunoglobulin; hydrophilic polymer such as polyvinylpyrrolidone; glycine, glutamine, asparagine, arginine , Amino acids such as stidine or lysine; monosaccharides such as glucose, mannose or dextrin, disaccharides or other carbohydrates, chelating agents such as EDTA, sugars such as sucrose, mannitol, trehalose or sorbitol, salt-forming counterions such as sodium; metal Complexes (eg Zn-protein complexes); and / or nonionic surfactants such as TWEEN ^™ , PLURONICS ^™ or polyethylene glycol (PEG).

  Here, the formulations may contain one or more active compounds as necessary for the particular indication being treated, preferably those with complementary activities that do not adversely affect each other. For example, it may be desirable to further provide an antibody that binds to vascular endothelial growth factor (VEGF), or EGFR, ErbB2 (eg, an antibody that binds to a different epitope of ErbB2), ErbB3, ErbB4 in certain formulations. Alternatively or in addition, the composition may contain a cytotoxic agent, cytokine or growth inhibitor. However, the cytotoxic agent is other than an anthracycline derivative such as doxorubicin or epirubicin. Such molecules are preferably present in combination in amounts that are effective for the purpose intended.

  The active ingredient can also be incorporated into colloidal drug delivery systems (e.g. liposomes, microcapsules prepared by coacervation or interfacial polymerization, e.g. hydroxymethylcellulose or gelatin-microcapsules and poly- (methyl methacrylate) microcapsules, respectively. Albumin microspheres, microemulsions, nanoparticles and nanocapsules) or macroemulsions. Such techniques are disclosed in Remington's Pharmaceutical Sciences, 16th edition, edited by A. Osol (1980).

  The formulation used for in vivo administration must be sterile. This is easily accomplished by filtration through a sterile filter membrane.

Sustained release preparations may be prepared. Suitable examples of sustained release preparations include solid hydrophobic polymer semipermeable matrices containing antibodies, which are in the form of shaped articles such as films or microcapsules. Examples of sustained release matrices include polyesters, hydrogels (eg, poly (2-hydroxyethyl-methacrylate), or poly (vinyl alcohol), polylactide (US Pat. No. 3,773,919), L-glutamic acid and γ-ethyl-L- Glutamate copolymers, non-degradable ethylene-vinyl acetate, degradable lactic acid-glycolic acid copolymers such as LUPRON DEPOT ^™ (injectable microspheres consisting of lactic acid-glycolic acid copolymer and leuprolide acetate), and poly-D-(- ) -3-hydroxybutyric acid, polymers such as ethylene-vinyl acetate and lactic acid-glycolic acid can release molecules for over 100 days, while certain hydrogels release proteins for shorter time. If left in the body for a long time, it is denatured or aggregated by exposure to moisture at 37 ° C. Risk of loss or changes in immunogenicity, rational measures can be devised to achieve stability depending on the mechanism involved, eg, the aggregation mechanism is intermolecular S—S bonds by thio-disulfide exchange Once found, the sulfhydryl residue is modified, lyophilized from an acidic solution, adjusted to moisture content, used with appropriate additives, and the stabilization is achieved by developing a specific polymer matrix composition be able to.

IV. Treatment with anti-ErbB2 antibodies According to the present invention, it is contemplated to use anti-ErbB2 antibodies for the treatment of various medical conditions characterized by overexpression and / or activation of ErbB2 receptors. Examples of medical conditions or diseases include benign or malignant tumors (e.g., renal, liver, kidney, bladder, breast, stomach, ovary, colorectal, prostate, pancreas, lung, vulva, thyroid, hepatic carcinoma). Sarcomas; glioblastomas and various types of head and neck tumors); leukemias and lymphoid malignancies; neurons, glia, astrocytes, hypothalamus and other glands, macrophages, epithelium, stroma And diseases of the split space; and inflammation, blood vessel-derived and immune diseases.

  The antibody of the present invention is administered in a known manner, for example, intravenously as a bolus or by continuous infusion over a period of time, intramuscular, intraperitoneal, intracerebral spinal, subcutaneous, intraarticular, intrasynovial, intrathecal, intraoral Administered to human patients by topical or inhalation route. Intravenous administration of the antibody is preferred.

  The therapeutic method of the present invention includes administering a combination of a chemotherapeutic agent other than an anthracycline derivative and an anti-ErbB2 antibody. Combination administration includes either simultaneous preparation using separate preparations or a single pharmaceutical formulation, and preferably both (or all) active agents have time to exert their biological activity simultaneously in either order. Of continuous administration. The preparation and administration schedule of such chemotherapeutic agents is used according to the manufacturer's instructions or determined empirically by skilled practitioners. The preparation and administration schedule of such chemotherapy is described in Chemotherapy Service M.C.Perry, Williams & Wilkins, Baltimore, MD (1992). The chemotherapeutic agent is given before, after, or concurrently with the administration of the antibody. The antibody may also be combined with an anti-estrogenic compound, such as tamoxifen or an antiprogesterone, such as onapristone (see European Patent 616812) at a known dosage for such molecules.

  It may also be desirable to administer antibodies against other tumor-associated antigens, such as antibodies that bind to EGFR, ErbB3, ErbB4, or vascular endothelial growth factor (VEGF). Alternatively, or in addition, two or more anti-ErbB2 antibodies may be co-administered to the patient. Often it is also beneficial to administer one or more cytokines to the patient. In a preferred embodiment, ErbB2 antibody is co-administered with a growth inhibitor. For example, a growth inhibitor is administered first, followed by an ErbB2 antibody. However, concomitant administration or ErbB2 antibody administration may be performed first. Suitable dosages for growth inhibitors are those currently used and can be reduced depending on the combined action (synergistic action) of the growth inhibitor and anti-ErbB2 antibody.

  Appropriate doses of antibodies for the prevention or treatment of illness, as described above, are the type of illness being treated, the severity and process of the illness, whether the antibody is administered for prevention or therapeutic purposes, It will depend on past treatment, patient clinical history and antibody responsiveness, and the discretion of the treating physician. The antibody is suitably administered to the patient at one time or over a series of treatments.

Depending on the type and severity of the disease, for example, one or more separate doses or continuous infusions, about 1 μg / kg to 15 mg / kg (eg, 0.1-20 mg / kg) of antibody is administered to the patient. Candidate for first dose. Depending on the factors discussed above, typical daily dosages range from about 1 μg / kg to 100 mg / kg or more. For repeated administrations over several days or longer, depending on the condition, the treatment is sustained until a desired suppression of disease symptoms occurs. However, other dosing schedules may be effective. The progress of this therapy is easily monitored by conventional techniques and assays.
Further information on appropriate dosages is provided in the examples below.

V. Articles of Manufacture In another embodiment of the invention, an article of manufacture containing materials useful for the treatment of the aforementioned diseases is provided. The article of manufacture comprises a container, a label and a package insert. Suitable containers include, for example, bottles, glass bottles, syringes and the like. The container can be formed of various materials such as glass or plastic. The container contains a composition effective for the treatment of a medical condition and has a sterilized doorway (e.g., the container is a bag or glass bottle for intravenous solutions with a stopper pierceable by a hypodermic needle. Good). At least one active agent in the composition is an anti-ErbB2 antibody. The label on or associated with the container indicates that the composition is used for the treatment of the selected medical condition. The article of manufacture further comprises a second container containing a pharmaceutically acceptable buffer, such as phosphate buffered saline, Ringer's solution and dextrose solution. It may further include other materials desirable from a commercial and user standpoint, including other buffers, diluents, filters, needles, and syringes. In addition, the article of manufacture includes a package insert with instructions that include a warning that the composition should not be used in combination with an anthracycline-type chemotherapeutic agent such as doxorubicin or epirubicin.

Deposit of materials The following hybridoma cell lines were deposited with the American Type Culture Collection 12301 Parklawn Drive, Rockville, MD, USA (ATCC).
Antibody name ATCC number Deposit date 7C2 ATCC HB-12215 October 17, 1996 7F3 ATCC HB-12216 October 17, 1996 4D5 ATCC CRL 10463 May 24, 1990

  Further details of the invention are illustrated by the following non-limiting examples.

(Example)
Materials and Methods Anti-ErbB2 Monoclonal Antibody Anti-ErbB2 IgG ₁ kappa mouse monoclonal antibody 4D5 specific for the extracellular domain of ErbB2 has been described in Fendly et al., Cancer Research 5o: 1550-1558 (1990) and WO 89/06692. Produced like that. Briefly, NIH3T3 / HER2-3 ₄₀₀ cells (approximately 1 × 10 ⁵ ErbB2 molecules / cell produced as described in Hudziak et al., Proc. Natl. Acad. Sci. (USA) 84: 7159 (1987). Were collected in phosphate buffered saline (PBS) containing 25 mM EDTA and used to immunize BALB / c mice. Mice were injected intraperitoneally at 0, 2, 5 and 7 weeks with 10 ⁷ cells in 0.5 ml PBS. Mice bearing antisera immunoprecipitated with ³² P-labeled ErbB2 were injected intraperitoneally with wheat germ agglutinin-Sepharose (WGA) purified ErbB2 membrane extract at 9 and 13 weeks. Subsequently, 0.1 ml of ErbB2 preparation was injected intravenously and splenocytes were fused with mouse myeloma line X63-Ag8.653. Hybridoma supernatants were screened for ErbB2 binding by ELISA and radioimmunoprecipitation. MOPC-21 (IgG1) (Cappell, Durham, NC) was used as an isotype matched control.

Treatment was carried out using the murine 4D5 antibody of humanized version (Herceptin (HERCEPTIN ^R)). Humanized antibodies were designed by inserting the complementarity determining region of the mouse 4D5 antibody into a common human immunoglobulin IgG ₁ (IgG ₁ ) framework (Carter et al., Proc. Natl. Acad. Sci. USA 89: 4285- 4289 [1992]). The resulting humanized anti-ErbB2 monoclonal antibody has a high affinity for p185 ^HER2 (Dillohiation constant [K _d ] = 0.1 nmol / L) and exhibits high levels of p185 ^HER2 in vitro and in human xenografts. Clinically as a single agent in ErbB2 overexpressing metastatic breast cancer patients who have markedly inhibited the growth of breast cancer cells, elicited antibody-dependent cellular cytotoxicity (ADCC), and have previously received extensive treatment It was found to be active. Herceptin® is produced by large-scale engineered Chinese hamster ovary (CHO) cell lines that secrete antibodies into the medium. The antibody is purified from the culture medium using standard chromatography and filtration methods. Each lot of antibody used in this study was assayed and proved to meet the requirements of the Food and Drug Administration regarding identity, purity and efficacy, and sterility and safety.

Eligibility criteria Patients must meet all of the following criteria for study permission.
-Metastatic breast cancer-ErbB2 (HER2) oncogene overexpression (2+ to 3+ as measured by immunohistochemistry or fluorescence in situ hybridization (FISH)). [Tumb expression of ErbB2 was determined by immunohistochemical analysis of slices prepared from paraffin-preserved tumor blocks of patients as previously described (Slamon et al., [1987] and [1989], supra). Can be measured. The primary detection antibody used is a mouse 4D5 MAb with the same CDRs as the humanized antibody used for therapy. A tumor is considered to overexpress ErbB2 if at least 25% of the tumor cells show membrane staining characteristic of p185 ^HER2 ]).
-Diseases that can be measured two-dimensionally by radiography, physical examination or photography (including cytolytic bone lesions)
A measurable disease is any reproducible measurement at two orthogonal diameters by physical examination, X-ray (simple film), computed tomography (CT), nuclear magnetic resonance imaging (MRI), ultrasound or photography. It is defined as a lump.
Osteoblast metastasis, pleural effusion, or ascites was not considered measurable. The measurable lesion should have the largest diameter of at least 1 cm. A listing of assessment sites for metastatic disease and the number of lesions at the assessment site (eg lung) had to be recorded in an appropriate case record table (CRF). When many lung or liver lesions were present, the six largest lesions at that site were followed.
-Ability to understand and sign written written consent-Women over 18-Suitable candidates for simultaneous cytotoxic chemotherapy as evidenced by review of laboratory assessments of blood, kidney, liver and metabolic function Person

Exclusion criteria Patients with any of the following were excluded from the study:
− Previously received cytotoxic chemotherapy for metastatic breast cancer
The patient may have previously received hormonal therapy for metastatic disease or cytotoxic treatment in an adjuvant setting.
-A malignant tumor that has not been treated at the same time-A performance status on the Karnofsky scale of less than 60%-A pregnant or lactating woman; if not taking effective contraception as determined by the investigator For example, a woman who has a possibility of pregnancy-one that has breast cancer in both left and right (both major tumors must have 2+ or 3+ HER2 overexpression, or metastatic sites 2+ or 3+ HER2 overexpression Must have expression)
-Use of drugs under study or non-approved drugs within 30 days prior to study-Patients with clinically unstable or untreated metastases in the brain (for example, those requiring radiation therapy)
Based on the above criteria, 469 patients were selected and accepted for study. Half of the patients (classified by chemotherapy) were randomized and received Herceptin ^R antibody (see below).

Administration and dosage
On day 0 of the anti-ErbB2 antibody , 4 mg / kg of humanized anti-ErbB2 antibody (Herceptin ^{R 1} , H) was intravenously administered over a period of 90 minutes or more. Starting on day 7, patients received weekly doses of 2 mg / kg antibody (intravenous) over a period of 90 minutes.

If the chemotherapy illness did not progress, the patient received one of the two chemotherapy for a minimum of 6 cycles: a) cyclophosphamide and doxorubicin or epirubicin if the patient was not receiving anthracycline therapy in an adjuvant setting (AC), or b) Paclitaxel (T, Taxol ^R ) if the patient has received some anthracycline therapy in an adjuvant setting. The first dose of Herceptin ^R antibody preceded the first cycle of either chemotherapy 24 hours. If the first dose of antibody was well tolerated, the next dose of antibody was made immediately prior to chemotherapeutic agent administration. If the first dose of antibody was not well tolerated, the next infusion continued 24 hours prior to chemotherapeutic administration. In the opinion of the treating physician, patients were allowed to continue chemotherapy for more than 6 cycles if they continued to benefit from treatment.

Cyclophosphamide (600 mg / m ² ) was given intravenously over a minimum of 3 minutes or infused over a maximum of 2 hours.
Doxorubicin (60 mg / m ² ) or epirubicin (75 mg / m ² ) was given intravenously over a minimum of 3-5 minutes or infused over a maximum of 2 hours according to institutional protocols.

Paclitaxel (Taxol ^R), was given at a dose of 175 mg / ^{m 2} over a period of 3 hours by intravenous administration. All patients who received paclitaxel received 20 mg x 2 dexamethasone (or equivalent) orally 12 and 6 hours prior to paclitaxel; 50 mg diphenhydramine (or equivalent) intravenously 30 minutes before administration of paclitaxel ), And 30 minutes prior to the administration of paclitaxel, 300 mg dimethidine (or other H ₂ blocker) was pre-administered intravenously.

Response criteria
Progressive illness Objective evidence that any measurable lesion increases by 25% or more. Progressive diseases also include cases where new lesions appear. In the case of bone lesions, the degree of progression is defined by a 25% increase in objective measurements by simple film, CT, MRI; new lesions that are non-fracture signs; or the need for pain relief radiation therapy.

Complete response completes with a minimum of 4 weeks with disappearance of all radiographic and / or visually apparent tumors. A complete reaction of the skin and chest wall must be confirmed by biopsy.

At least 50% reduction in total measurable lesion orthogonal diameter product in a minimum of 4 weeks of partial response . No new lesions appear or any lesions do not grow.
Slight response Reduction of all measurable lesion orthogonal diameter products by 25% or 49%. No new lesions appear or any lesions do not grow.

Stable disease measurable lesion size does not change more than 25%. The lesion did not appear.
Tumor progression time (TTP) was calculated from the start of treatment to progression. Response speed confidence limits were calculated using a rigorous method for a single proportion (Fleiss, JL, Statistical Methods for Rates and Proportions (2nd edition), New York, Wiley, 1981, pp13-17).

Results As a result of assessing disease progression time (monthly TTP) and response rate (RR) in a median follow-up of 10.5 months, Herceptin (registration) increased without increasing overall undesirable events (AE) (Trademark) showed a markedly enhanced chemotherapeutic effect:
Number of registrations TTP (month) RR (%) AE (%)
CRx 234 5.5 36.2 66
CRx + H 235 8.6 ^★ 62.00 ^★★ 69
AC 145 6.5 42.1 71
AC + H 146 9.0 64.9 68
T 89 4.2 25.0 59
T + H 89 7.1 57.3 70
^★ p <0.001 in log-rank test
^★★ X ² test with p <0.01
CRx: chemotherapy AC: anthracycline / cyclophosphamide treatment H: Herceptin ^R
T: Taxol ^R

A combination of AC + T (18% grade 3/4) with myocardial dysfunction syndrome similar to that observed with anthracyclines than with AC alone (3%), T (0%) or T + H (2%) It has been reported that it is more common in the case of treatment.
These data show that the combination of chemotherapy and anti-ErbB2 antibody treatment significantly increases the clinical benefit as assessed by assessment of response speed and disease progression. However, the combined use of anthracyclines for anti-ErbB2 antibody therapy is contraindicated because of the increased side effects on the heart caused by doxorubicin or epirubicin. As a result of considering the risks and benefits, a combination treatment of Herceptin ^R and paclitaxel (Taxol ^R ) is preferred.
The disclosures of all cited references in the specification are expressly incorporated herein by reference.

(Sequence Listing)
<110> Genentech, Inc. <120> Treatment Method Using Anti-ErbB2 Antibody <130> P1256R2PCT
<150> US 60/0669346
<151> 1997-12-12
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<212> PRT
<213> Homo sapiens <400> 1
Cys Thr Gly Thr Asp Met Lys Leu Arg Leu Pro Ala Ser Pro Glu 1 5 10 15 Thr His Leu Asp Met Leu Arg His Leu Tyr Gln Gly Cys Gln Val 20 25 30 Val Gln Gly Asn Leu Glu Leu Thr Tyr Leu Pro Thr Asn Ala Ser 35 40 45 Leu Ser Phe Leu Gln Asp Ile Gln Glu Val Gln Gly Tyr Val Leu 50 55 60 Ile Ala His Asn Gln Val Arg Gln Val Pro Leu Gln Arg Leu Arg 65 70 75 Ile Val Arg Gly Thr Gln Leu Phe Glu Asp Asn Tyr Ala Leu Ala 80 85 90 Val Leu Asp Asn Gly Asp Pro Leu Asn Asn Thr Thr Pro Val Thr 95 100 105 Gly Ala Ser Pro Gly Gly Leu Arg Glu Leu Gln Leu Arg Ser Leu 110 115 120 Thr Glu Ile Leu Lys Gly Gly Val Leu Ile Gln Arg Asn Pro Gln 125 130 135 Leu Cys Tyr Gln Asp Thr Ile Leu Trp Lys Asp Ile Phe His Lys 140 145 150 Asn Asn Gln Leu Ala Leu Thr Leu Ile Asp Thr Asn Arg Ser Arg 155 160 165 Ala 166

<210> 2
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Ser Thr Gln Val Cys Thr Gly Thr Asp Met Lys Leu Arg Leu Pro 1 5 10 15 Ala Ser Pro Glu Thr His Leu Asp Met Leu Arg His Leu Tyr Gln 20 25 30 Gly Cys 32

<210> 3
<211> 11
<212> PRT
<213> Homo sapiens <400> 3
Pro Lys Asn Ser Ser Met Ile Ser Asn Thr Pro 1 5 10 11
<210> 4
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<212> PRT
<213> Homo sapiens <400> 4
His Gln Ser Leu Gly Thr Gln 1 5 7

<210> 5
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<212> PRT
<213> Homo sapiens <400> 5
His Gln Asn Leu Ser Asp Gly Lys 1 5 8

<210> 6
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<212> PRT
<213> Homo sapiens <400> 6
His Gln Asn Ile Ser Asp Gly Lys 1 5 8

<210> 7
<211> 8
<212> PRT
<213> Homo sapiens <400> 7
Val Ile Ser Ser His Leu Gly Gln 1 5 8

<210> 8
<211> 59
<212> PRT
<213> Homo sapiens <400> 8
Val Glu Glu Cys Arg Val Leu Gln Gly Leu Pro Arg Glu Tyr Val 1 5 10 15 Asn Ala Arg His Cys Leu Pro Cys His Pro Glu Cys Gln Pro Gln 20 25 30 Asn Gly Ser Val Thr Cys Phe Gly Pro Glu Ala Asp Gln Cys Val 35 40 45 Ala Cys Ala His Tyr Lys Asp Pro Pro Phe Cys Val Ala Arg 50 55 59

<210> 9
<211> 65
<212> PRT
<213> Homo sapiens <400> 9
Leu Pro Cys His Pro Glu Cys Gln Pro Gln Asn Gly Ser Val Thr 1 5 10 15 Cys Phe Gly Pro Glu Ala Asp Gln Cys Val Ala Cys Ala His Tyr 20 25 30 Lys Asp Pro Pro Phe Cys Val Ala Arg Cys Pro Ser Gly Val Lys 35 40 45 Pro Asp Leu Ser Tyr Met Pro Ile Trp Lys Phe Pro Asp Glu Glu 50 55 60 Gly Ala Cys Gln Pro 65

Cleavage mutant analysis and site-directed mutagenesis (Nakamura et al., J. of Virology 67 (10): 6179-6191 [October 1993]; Renz et al., J. Cell Biol. 125 (6): 1395- 1406 [June 1994]) shows the epitope mapping of the extracellular domain of ErbB2. Antiproliferative MAbs 4D5 and 3H4 are bound adjacent to the transmembrane domain. Various ErbB2-ECD truncations or point mutations were prepared from cDNA using the polymerase chain reaction method. The ErbB2 mutant was expressed as a gD fusion protein in a mammalian expression plasmid. As this expression plasmid, a cytomegalovirus promoter / enhancer having a polyadenylation signal and SV40 terminal located downstream of the inserted cDNA is used. Plasmid DNA was transfected into 293S cells. One day after transfection, cells were metabolically labeled overnight in low glucose DMEM free of methionine and cysteine free of ³⁵ S methionine and ³⁵ S cysteine each with 25 uCi and 1% dialyzed fetal calf serum. The supernatant was collected and either ErbB2 MAb or control antibody was added to the supernatant and incubated at 4 ° C. for 2-4 hours. The complex was precipitated and applied to a 10-20% Tricine SDS gradient gel and electrophoresed at 100V. The gel was electroblotted onto the membrane and analyzed by autoradiography. SEQ ID NOs: 8 and 9 represent 3H4 and 4D5 epitopes, respectively. The amino acid sequence of ErbB2 domain 1 (SEQ ID NO: 1) is underlined. Bold amino acids indicate the position of the epitope recognized by MAbs 7C2 and 7F3 determined by deletion mapping, ie, the “7C2 / 7F3 epitope” (SEQ ID NO: 2).

Claims (19)

In a disease characterized by overexpression of the ErbB2 receptor comprising administering to a human patient an effective amount of a combination of an anti-ErbB2 antibody and a chemotherapeutic agent other than an anthracycline derivative in the absence of an anthracycline derivative. A method for treating a prone human or a human patient diagnosed with the disease. 2. The method of claim 1, wherein the disease is a benign or malignant tumor. 2. The method of claim 1, wherein the disease is cancer. The cancer is breast cancer, squamous cell carcinoma, small cell lung cancer, non-small cell lung cancer, gastrointestinal cancer, pancreatic cancer, glioblastoma, cervical cancer, ovarian cancer, liver cancer, bladder cancer, hepatocellular carcinoma, colon cancer 4. Colorectal cancer, endometrial cancer, salivary gland cancer, renal cancer, prostate cancer, vulvar cancer, thyroid cancer, liver carcinoma and various types of head and neck cancers. Method. The method of claim 4, wherein the cancer is breast cancer. 6. The method of claim 5, wherein the cancer is metastatic breast cancer. 2. The method of claim 1, wherein said antibody binds to the extracellular domain of ErbB2 receptor. 8. The method of claim 7, wherein the antibody binds to epitope 4D5 of the ErbB2 extracellular domain sequence. 9. The method of claim 8, wherein the antibody is a humanized 4D5 anti-ErbB2 antibody. 2. The method of claim 1, wherein the chemotherapeutic agent is a taxoid. 11. The method of claim 10, wherein the taxoid is paclitaxel or docetaxel. 2. The method of claim 1, wherein the effective amount of the combination is less than the sum of the effective amounts of the anti-ErbB2 antibody and the chemotherapeutic agent when administered individually as a single agent. The method of claim 1, wherein efficacy is measured by determining disease progression time and response rate. An article of manufacture comprising a container, a composition in the container containing an anti-ErbB2 antibody, and a package insert containing instructions to avoid the use of an anthracycline-type chemotherapeutic agent in combination with the composition. 15. The article of manufacture of claim 14, further comprising a label on or with the container indicating that the composition can be used to treat a condition characterized by overexpression of ErbB2 receptor. 16. The article of manufacture of claim 15, wherein the label indicates that the composition can be used to treat breast cancer. The article of manufacture of claim 15, wherein said anti-ErbB2 antibody is bound to the extracellular domain of a receptor. 18. The article of manufacture of claim 17, wherein the anti-ErbB2 antibody binds to epitope 4D5 of the ErbB2 extracellular domain sequence. 19. The article of manufacture of claim 18, wherein said antibody is a humanized 4D5 anti-ErbB2 antibody.

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